[Effects of macrophages on the biological behaviors and VEGF receptor mRNA, Hoxb2 mRNA, and integrin alphavbeta3 expressions of vascular endothelial cells].

PubMed

Liu, Liang; Liu, Xu-Sheng; Zhang, Xiao-Qi; Ming, Jia; Xu, Hui; Cheng, Tian-Min

2005-02-01

To explore the mechanism by which macrophages regulate angiogenesis by co-culturing human umbilical vein endothelial cells (ECV-304) with human macrophage cells (U937) stimulated by concanavalin A (ConA). Monolayer ECV-304 cells growing to 60% confluence were co-cultured with 1 x 10(5)/ml U937 cells in the presence or absence of ConA (ConA+U937+ECV-304 and U937+ECV-304 groups, respectively), with non-treated and ConA-treated ECV-304 cells serving as the control groups (ECV-304 and ConA+ECV-304 groups, respectively). Forty-eight h later, U937 cells were removed from the cell co-culture for examining changes in DNA synthesis of ECV-304 cells with (3)H-TdR incorporation assay and for cell cycle analysis with flow cytometry. RT-PCR was employed to assess the influence of macrophages stimulated by ConA on the expression of the target genes. With immunofluorescent method, the changes in the expression of integrin receptor alphavbeta3 of ECV-304 were determined. A significant increase in S-phase ECV-304 cells with enhanced DNA synthesis was observed after co-culture of the cells with ConA-stimulated U937 cells (P<0.01), which also resulted in significant up-regulation of the expressions of KDR mRNA (0.879+/-0.003), Hoxb2 mRNA (0.947+/-0.003) and integrin receptor alphavbeta3 (10.26+/-1.73). Macrophages can accelerate the proliferation, migration and adhesion of the vascular endothelial cells to the basilar membrane matrix by affecting their cell cycle, DNA synthesis, expression of KDR mRNA, Hoxb2 mRNA and integrin alphavbeta3, so as to modulate the angiogenetic process of the latter cells.

Agaritine from Agaricus blazei Murrill induces apoptosis in the leukemic cell line U937.

PubMed

Akiyama, Hidehiko; Endo, Masahiro; Matsui, Taei; Katsuda, Itsurou; Emi, Nobuhiko; Kawamoto, Yasuko; Koike, Takaaki; Beppu, Hidehiko

2011-05-01

Agaricus blazei Murrill (ABM) has been shown to exhibit immunostimulatory and anti-cancer activities; however, its mechanism of action is poorly understood. We recently found that the diffusible fraction of hot-water extract of ABM exhibits anti-tumor activity toward leukemic cells, and identified it as agaritine, a hydrazine-containing compound. In the present study, we examined the morphological and cytochemical effects of agaritine on U937 cells to elucidate the tumoricidal mechanism of agaritine. Surface expression of phosphatidylserine (evaluated by annexin V binding), Fas antigen, DNA cleavage using TUNEL staining, changes in caspase activities and cytochrome c release, before and after treatment with agaritine, were examined using U937 cells. Nuclear damage, DNA fragmentation, was observed by Wright-Giemsa, TUNEL staining and agarose gel electrophoresis when U937 cells were incubated with 10μg/mL of agaritine for 48h. Flow cytometric analysis indicated that agaritine augments the proportion of annexin V-positive U937 cells without significant change in Fas antigen expression. Activities of caspase-3, -8 and -9 were gradually increased after the addition of agaritine. In the presence of caspase-3 or granzyme B inhibitor, except for the caspase-8 inhibitor, annexin V expression was significantly decreased, suggesting that mainly caspase-3 and -9 participate in the apoptotic pathway. Furthermore, cytochrome c release was detected by western blotting analysis after agaritine treatment. These results strongly suggest that the ABM constituent agaritine moderately induces apoptosis in U937 leukemic cells via caspase activation through cytochrome c release from mitochondria. This is the first report suggesting that the anti-tumor effect of agaritine is mediated through apoptosis. The present results might provide helpful suggestions for the design of anti-tumor drugs toward leukemia patients. Copyright © 2011 Elsevier B.V. All rights reserved.

Potential mechanisms of cytosolic calcium modulation in interferon-gamma treated U937 cells

NASA Technical Reports Server (NTRS)

Klein, Jon B.; Mcleish, Kenneth R.; Sonnenfeld, Gerald; Dean, William L.

1987-01-01

The ability of interferon-gamma (IFN-gamma) to alter cytoplasmic Ca(2+) content in the monocytelike cell line U937 was investigated, using a slow Ca-channel blocker, diltiazem. In addition, the Ca-ATPase and the Ca-uptake activities were measured in isolated U937 membranes, together with the effect of inositol trisphosphate (IP3) upon the Ca(2+) release from Ca-loaded membranes. The addition of 50 U/ml INF-gamma to U937 cultures was found to increase internal Ca(2+) by about 100 percent within 3 min. The increase was significantly reduced by incubation in Ca-free buffer or by the addition of diltiazem. A crude membrane preparation from U937 cells was found to contain significant amounts of Ca-ATPase activity and to sequester Ca(2+) to a level of 8 nmol/mg in 30 sec; the addition of IP3 induced release of a portion of the sequestered Ca(2+) which was then resequestered. The results suggest that IFN-gamma causes an increase of cytoplasmic Ca(2+), in part, by the IP3-induced release from the internal storage sites and, in part, from the entry of extracellular Ca through slow channels.

Induction of cytosine arabinoside-resistant human myeloid leukemia cell death through autophagy regulation by hydroxychloroquine.

PubMed

Kim, Yundeok; Eom, Ju-In; Jeung, Hoi-Kyung; Jang, Ji Eun; Kim, Jin Seok; Cheong, June-Won; Kim, Young Sam; Min, Yoo Hong

2015-07-01

We investigated the effects of the autophagy inhibitor hydroxychloroquine (HCQ) on cell death of cytosine arabinoside (Ara-C)-resistant human acute myeloid leukemia (AML) cells. Ara-C-sensitive (U937, AML-2) and Ara-C-resistant (U937/AR, AML-2/AR) human AML cell lines were used to evaluate HCQ-regulated cytotoxicity, autophagy, and apoptosis as well as effects on cell death-related signaling pathways. We found that HCQ-induced dose- and time-dependent cell death in Ara-C-resistant cells compared to Ara-C-sensitive cell lines. The extent of cell death and features of HCQ-induced autophagic markers including increase in microtubule-associated protein light chain 3 (LC3) I conversion to LC3-II, beclin-1, ATG5, as well as green fluorescent protein-LC3 positive puncta and autophagosome were remarkably greater in U937/AR cells. Also, p62/SQSTM1 was increased in response to HCQ. p62/SQSTM1 protein interacts with both LC3-II and ubiquitin protein and is degraded in autophagosomes. Therefore, a reduction of p62/SQSTM1 indicates increased autophagic degradation, whereas an increase of p62/SQSTM1 by HCQ indicates inhibited autophagic degradation. Knock down of p62/SQSTM1 using siRNA were prevented the HCQ-induced LC3-II protein level as well as significantly reduced the HCQ-induced cell death in U937/AR cells. Also, apoptotic cell death and caspase activation in U937/AR cells were increased by HCQ, provided evidence that HCQ-induced autophagy blockade. Taken together, our data show that HCQ-induced apoptotic cell death in Ara-C-resistant AML cells through autophagy regulation. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Induction of Programmed Cell Death by Parvovirus H-1 in U937 Cells: Connection with the Tumor Necrosis Factor Alpha Signalling Pathway

PubMed Central

Rayet, Béatrice; Lopez-Guerrero, José-Antonio; Rommelaere, Jean; Dinsart, Christiane

1998-01-01

The human promonocytic cell line U937 undergoes apoptosis upon treatment with tumor necrosis factor alpha (TNF-α). This cell line has previously been shown to be very sensitive to the lytic effect of the autonomous parvovirus H-1. Parvovirus infection leads to the activation of the CPP32 ICE-like cysteine protease which cleaves the enzyme poly(ADP-ribose)polymerase and induces morphologic changes that are characteristic of apoptosis in a way that is similar to TNF-α treatment. This effect is also observed when the U937 cells are infected with a recombinant H-1 virus which expresses the nonstructural (NS) proteins but in which the capsid genes are replaced by a reporter gene, indicating that the induction of apoptosis can be assigned to the cytotoxic nonstructural proteins in this cell system. The c-Myc protein, which is overexpressed in U937 cells, is rapidly downregulated during infection, in keeping with a possible role of this product in mediating the apoptotic cell death induced by H-1 virus infection. Interestingly, four clones (designated RU) derived from the U937 cell line and selected for their resistance to H-1 virus (J. A. Lopez-Guerrero et al., Blood 89:1642–1653, 1997) failed to decrease c-Myc expression upon treatment with differentiation agents and also resisted the induction of cell death after TNF-α treatment. Our data suggest that the RU clones have developed defense strategies against apoptosis, either by their failure to downregulate c-Myc and/or by activating antiapoptotic factors. PMID:9765434

Anti-CHMP5 single chain variable fragment antibody retrovirus infection induces programmed cell death of AML leukemic cells in vitro.

PubMed

Wang, Hai-rong; Xiao, Zhen-yu; Chen, Miao; Wang, Fei-long; Liu, Jia; Zhong, Hua; Zhong, Ji-hua; Ou-Yang, Ren-rong; Shen, Yan-lin; Pan, Shu-ming

2012-06-01

Over-expressed CHMP5 was found to act as oncogene that probably participated in leukemogenesis. In this study, we constructed the CHMP5 single chain variable fragment antibody (CHMP5-scFv) retrovirus and studied the changes of programmed cell death (PCD) of AML leukemic cells after infection by the retrovirus. The anti-CHMP5 KC14 hybridoma cell line was constructed to generate monoclonal antibody of CHMP5. The protein expression of CHMP5 was studied using immunofluorescence analysis. pMIG-CHMP5 scFv antibody expressible retroviral vector was constructed to prepare CHMP5-scFv retrovirus. AML leukemic U937 cells were infected with the retrovirus, and programmed cell death was studied using confocal microscope, FCM and Western blot. We obtained a monoclonal antibody of CHMP5, and found the expression of CHMP5 was up-regulated in the leukemic cells. After U937 cells were infected with CHMP5-scFv retrovirus, CHMP5 protein was neutralized. Moreover, the infection resulted in a significant increase in apoptosis and necrosis of U937 cells. In U937 cells infected with CHMP5-scFv retrovirus, apoptosis-inducing factor (AIF)-mediated caspase-independent necrotic PCD was activated, but autophagic programmed cell death was not observed. Neither the intrinsic nor extrinsic apoptotic PCD pathway was activated. The granzyme B/perforin-mediated caspase-dependent apoptotic PCD pathway was not activated. CHMP5-scFv retrovirus can neutralize the abnormally high levels of the CHMP5 protein in the cytosol of AML leukemic U937 cells, thereby inducing the programmed cell death of the leukemic cells via AIF-mediated caspase-independent necrosis and apoptosis.

Regulation of the steady state level of Fc gamma RI mRNA by IFN-gamma and dexamethasone in human monocytes, neutrophils, and U-937 cells.

PubMed

Pan, L Y; Mendel, D B; Zurlo, J; Guyre, P M

1990-07-01

The high affinity IgG FcR Fc gamma RI, CD64, plays important roles in the immune response. Fc gamma RI is predominantly expressed on monocytes and macrophages, and barely detectable on neutrophils. rIFN-gamma markedly increases the expression of Fc gamma RI on neutrophils, monocytes, macrophages and myeloid cell lines such as U-937, HL-60, and THP-1. Glucocorticoids inhibit the augmentation of Fc gamma RI expression by rIFN-gamma on neutrophils and myeloid cell lines, but enhance the augmentation of Fc gamma RI expression by rIFN-gamma on monocytes. In this study, we examined the effect of rIFN-gamma and dexamethasone (Dex) on the steady state level of Fc gamma RI mRNA in U-937 cells, neutrophils, and monocytes by hybridizing total RNA with the Fc gamma RI cDNA probe, p135. We found that the amount of Fc gamma RI mRNA increased within 1 h of treatment with rIFN-gamma in all three cell types. This initial induction of Fc gamma RI mRNA by rIFN-gamma was completely blocked by an inhibitor of RNA synthesis, actinomycin D, suggesting that the rIFN-gamma-mediated induction of Fc gamma RI mRNA is dependent on gene transcription. Dex, used in combination with rIFN-gamma, partially blocked the induction of Fc gamma RI mRNA by rIFN-gamma in U-937 cells and neutrophils, but caused a synergistic increase in Fc gamma RI mRNA levels in monocytes. The inhibitory effect of Dex on the steady state level of Fc gamma RI mRNA in U-937 cells was blocked by an inhibitor of protein synthesis, cycloheximide, suggesting that Dex-induced proteins were involved in the regulation of Fc gamma RI expression. This study indicates that the regulation of Fc gamma RI expression on U-937 cells, neutrophils, and monocytes by rIFN-gamma and Dex occurs, at least in part, at the mRNA level. rIFN-gamma increases the steady state level of Fc gamma RI mRNA through a common pathway among U-937 cells, neutrophils, and monocytes, whereas the effect of Dex on rIFN-gamma-induced Fc gamma RI mRNA is cell-type specific.

miR-211 Plays a Critical Role in Cnidium officinale Makino Extract-Induced, ROS/ER Stress-Mediated Apoptosis in U937 and U266 Cells

PubMed Central

Cha, Jin Ah; Song, Hyo-Sook; Kang, Beomku; Park, Moon Nyeo; Park, Kyoung Sun; Shim, Bum-Sang

2018-01-01

Though Cnidium officinale Makino (COM) was known to have anti-angiogenic, anti-oxidant, neuroprotective, and anti-cancer effects, the underlying anticancer mechanism of COM using endoplasmic reticulum (ER) stress and miRNA remained unclear until now. Thus, in the current study, the inhibitory mechanism of COM in lymphoma and multiple myeloma (MM) cells was elucidated. COM exerted cytotoxicity in U937 and U266 but not Raw264.7 cells. COM treatment increased the expression of ER stress-related proteins such as p-protein kinase RNA-like endoplasmic reticulum kinase (p-PERK), p-eukaryotic initiation factor (p-eIF2α), and activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP). COM also cleaved poly (ADP-ribose) polymerase (PARP) in a dose-dependent manner in both cells. Also, reactive oxygen species (ROS) generation was elevated by COM treatment. Conversely, the apoptotic effect of COM treatment was blocked by N-acetyl-l-cysteine (NAC) pretreatment. Also, the pro-survival miRNA, miR-211 was decreased by COM treatment in U937 and U266 cells. miR-211 mimic attenuated COM-induced apoptosis. Taken together, these results support the scientific evidence that COM induces apoptosis via ROS generation/CHOP activation and miR-211 suppression in U937 and U266 cells. PMID:29543750

Synergism between arsenite and proteasome inhibitor MG132 over cell death in myeloid leukaemic cells U937 and the induction of low levels of intracellular superoxide anion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lombardo, Tomás; Cavaliere, Victoria; Costantino, Susana N.

Increased oxygen species production has often been cited as a mechanism determining synergism on cell death and growth inhibition effects of arsenic-combined drugs. However the net effect of drug combination may not be easily anticipated solely from available knowledge of drug-induced death mechanisms. We evaluated the combined effect of sodium arsenite with the proteasome inhibitor MG132, and the anti-leukaemic agent CAPE, on growth-inhibition and cell death effect in acute myeloid leukaemic cells U937 and Burkitt's lymphoma-derived Raji cells, by the Chou–Talalay method. In addition we explored the association of cytotoxic effect of drugs with changes in intracellular superoxide anion (O{submore » 2}{sup −}) levels. Our results showed that combined arsenite + MG132 produced low levels of O{sub 2}{sup −} at 6 h and 24 h after exposure and were synergic on cell death induction in U937 cells over the whole dose range, although the combination was antagonistic on growth inhibition effect. Exposure to a constant non-cytotoxic dose of 80 μM hydrogen peroxide together with arsenite + MG132 changed synergism on cell death to antagonism at all effect levels while increasing O{sub 2}{sup −} levels. Arsenite + hydrogen peroxide also resulted in antagonism with increased O{sub 2}{sup −} levels in U937 cells. In Raji cells, arsenite + MG132 also produced low levels of O{sub 2}{sup −} at 6 h and 24 h but resulted in antagonism on cell death and growth inhibition. By contrast, the combination arsenite + CAPE showed high levels of O{sub 2}{sup −} production at 6 h and 24 h post exposure but resulted in antagonism over cell death and growth inhibition effects in U937 and Raji cells. We conclude that synergism between arsenite and MG132 in U937 cells is negatively associated to O{sub 2}{sup −} levels at early time points after exposure. -- Highlights: ► Arsenic combined cytotoxic and anti-proliferative effects by Chou–Talalay method. ► Cytotoxic effect associated with superoxide levels as assessed by flow cytometry. ► Synergism between arsenite and MG132 in U937 leukemia cell line. ► Synergism turned into antagonism by low levels of hydrogen peroxide. ► Resistance to arsenic cytotoxicity linked to early superoxide anion increased levels.« less

Reversible differentiation of human monoblastic leukemia U937 cells by ML-9, an inhibitor of myosin light chain kinase.

PubMed

Yamamoto-Yamaguchi, Y; Makishima, M; Kanatani, Y; Kasukabe, T; Honma, Y

1996-05-01

Human monoblastic leukemia U937 cells are induced to differentiate into monocytes and macrophages by various agents. We have shown that 1-(5-chloronaphthalene-1-sulfonyl)-1H-hexahydro-1,4-diazepine hydrochloride (ML-9), an inhibitor of myosin light chain kinase, induces differentiation of monocytoid leukemia cell lines U937 and THP-1 but not of myeloblastic leukemic ML-1 cell or erythroleukemia K562 cells. In the present study, we further analyzed the effect of ML-9 in comparison with that of 1 alpha, 25-dihydroxyvitamin D3 (VD3) a typical inducer of monocytic differentiation. ML-9 induced nitroblue tetrazolium (NBT)-reducing activity of U937 cell more rapidly than VD3: This differentiation marker was induced significantly after incubation with ML-9 and VD3 for 4 hours and 1 day, respectively. ML-9 also induced alpha-naphthyl acetate esterase (ANAE) activity, another monocytic differentiation marker, more rapidly than VD3. The maximum levels of these markers induced by ML-9 were comparable to those induced by VD3, but after removal of ML-9 from the medium by washing the cells, the expressions of theses markers decreased within 4 hours and reached basal levels in 1 day, indicating that ML-9's induction of expression of differentiation-associated phenotypes was reversible. The growth inhibition of U937 cells by ML-9 was also reversible. Similar effects were observed in another line of human monoblastic cells, THP-1. ML-9 had little or no effect on the morphology of U937 cells but increased the expression of monocyte-macrophage lineage-associated surface antigen, CD14, to some extent. Irreversible terminal differentiation induced by VD3 is associated with down regulation of the expression of c-myc and upregulation of the expression of c-fos and c-jun, but ML-9 did not affect the expression of these oncogenes appreciably. ML-9-induced differentiation was also reversible when the cells were cultured with cultured with ML-9 plus an anti-cancer drug such as 1-beta-D-arabino-furanosylcytosine or daunomycin. it became irreversible, however, upon simultaneous treatment with dexamethasone and transforming growth factor-beta 1 (TGF-beta 1), which did not induce differentiation of U937 cells but caused growth arrest of the cells in the G0/G1 phase of the cell cycle. These results suggest that ML-9 should be useful for studying the mechanisms of monocytic differentiation.

Para-Nonylphenol Induces Apoptosis of U937 Human Monocyte Leukemia Cells in vitro.

PubMed

Santa, Kazuki; Ohsawa, Tomonori; Sakimoto, Takehiko

2016-01-01

Human autoimmune diseases are caused by a variety of factors, such as environmental chemicals, including para-nonylphenol. Macrophages play many critical roles in the regulation of immunity and the progression of autoimmune diseases. However, little information is available regarding the effects of para-nonylphenol on cellular signaling pathways and the death of these cells in vitro. Here, we show that very high concentrations of para-nonylphenol (50-100 μM) induce apoptosis in U937 human monocyte leukemia cells in a dose-dependent manner. Cell viability was judged using the trypan blue exclusion method. FACS analysis for DNA fragmentation was conducted, cellular signaling pathways were evaluated using western blot analysis, and caspase activity was measured by using substrates. U937 cells were differentiated by PMA. Treatment with > 50 μM para-nonylphenol induced apoptosis in U937 monocyte cells and MCF- 7 and MDA-MB231 human breast cancer cells. We found cytochrome c release from the mitochondria to the cytoplasm, DNA fragmentation, and decreased expression of anti-apoptotic protein Bcl-XL. Caspase 3 and 9 were induced, but caspase 1 and 3-inhibitor treatment suppressed apoptosis. Para-nonylphenol decreased the levels of activated AKT and increased the levels of activated JNK/SAPK at 15 min after treatment. Furthermore, with PMA treatment, U937 cells were differentiated into a macrophage-like phenotype and showed attenuated cell death against para-nonylphenol. As this assay system is simple and rapid, it may represent a useful artificial tool to clarify the signaling pathways of apoptotic cell death in human monocytes in vitro. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

shRNA-mediated EMMPRIN silencing inhibits human leukemic monocyte lymphoma U937 cell proliferation and increases chemosensitivity to adriamycin.

PubMed

Gao, Hui; Jiang, Qixiao; Han, Yantao; Peng, Jianjun; Wang, Chunbo

2015-03-01

EMMPRIN is a widely distributed cell surface glycoprotein, which plays an important role in tumor progression and confers resistance to some chemotherapeutic drugs. Recent studies have shown that EMMPRIN overexpression indicates poor prognosis in acute myeloid leukemia (AML). However, little was known on the role of EMMPRIN in leukemia. Human leukemia cell line U937 was stably transfected with a EMMPRIN-targeted shRNA-containing vector to investigate the effect of EMMPRIN on cellular functions. EMMPRIN expression was monitored by qRT-PCR and Western blotting. Cell viability and proliferation were determined by trypan blue exclusion and BrdU labeling, respectively. Cell cycle and apoptosis were analyzed by flow cytometry. Cytotoxicity of chemotherapeutic agent adriamycin on cells was assessed by MTT assay. Knockdown of EMMPRIN gene significantly inhibited cell viability and decreased cell proliferation. Fluorescence-activated cell-sorting analysis revealed that the reduced EMMPRIN expression resulted in cell cycle arrest at G1 phase and induced apoptosis. Meanwhile, western blotting analysis showed that EMMPRIN knockdown was associated with downregulation of cell cycle- and apoptosis-related molecules including cyclin D1, cyclin E, as well as increase in cleavage of caspase-3 and PARP. This study also showed that silencing of EMMPRIN sensitized U937 cells to Adriamycin. EMMPRIN is involved in proliferation, growth, and chemosensitivity of human AML line U937, indicating that EMMPRIN may be a promising therapeutic target for AML.

Macrophage differentiation induced by PMA is mediated by activation of RhoA/ROCK signaling.

PubMed

Yang, Lifeng; Dai, Fan; Tang, Lian; Le, Yulan; Yao, Wenjuan

2017-01-01

In order to investigate the effects of RhoA/ROCK signaling in macrophage differentiation, we used 100 ng/mL PMA to induce macrophage differentiation from U937 cells in vitro. The observation of cell morphology and the expression of CD68 and SR-A were performed to confirm the differentiation induced by PMA. Western blot analysis showed that the expression of ROCK1 and ROCK2 and the phosphorylation of MYPT1 were significantly increased after PMA treatment. Pulldown assay showed that the activation of RhoA was obviously enhanced when U937 cells were treated with PMA. In order to further demonstrate whether RhoA/ROCK signaling could mediate the macrophage differentiation induced by PMA, we successfully suppressed the expression of RhoA, ROCK1 and ROCK2 by performing siRNA technology in U937 cells, respectively. The macrophage differentiation and the expression of CD68 and SR-A were significantly inhibited by the suppression of RhoA, ROCK1 or ROCK2 in PMA-induced U937 cells, indicating that the macrophage differentiation induced by PMA is associated with RhoA/ROCK signaling pathway. In addition, we pretreated U937 cells with Y27632 (ROCK inhibitor, 20 μM) for 30 min and then observed the macrophage differentiation induced by PMA. The result illustrated that Y27632 pretreatment obviously inhibited PMA-induced differentiation and the expression of CD68 and SR-A. In conclusion, the activation of RhoA/ROCK signaling is responsible for the macrophage differentiation induced by PMA.

Flavonoids from Orostachys japonicus A. Berger induces caspase-dependent apoptosis at least partly through activation of p38 MAPK pathway in U937 human leukemic cells.

PubMed

Lee, Won Sup; Yun, Jeong Won; Nagappan, Arulkumar; Jung, Ji Hyun; Yi, Sang Mi; Kim, Dong Hoon; Kim, Hye Jung; Kim, GonSup; Ryu, Chung Ho; Shin, Sung Chul; Hong, Soon Chan; Choi, Yung Hyun; Jung, Jin-Myung

2015-01-01

Orostachys japonicus A. Berger (A. Berger) is commonly used as a folk remedy for cancer therapy. However, the mechanisms of its anti-cancer activity are poorly investigated in human cancer cells. In this study, we investigated whether flavonoids extracted from Orostachys japonicus A. Berger (FEOJ) might have anticancer effects in human leukemia cells, focusing on cell death mechanisms. U937 human leukemic cancer cells were used. FEOJ induced apoptosis in a dose-dependent manner in human U937 cancer cells. Flow cytometry revealed significant accumulation of cells with sub-G1 DNA content at the concentrations of 200 μg/mL and 400 μg/mL. FEOJ-induced apoptosis was caspase-dependent through loss of mitochondrial membrane potential (MMP, ΔΨm) in human U937 cancer cells, which might be associated with suppression of Bcl-2 and XIAP proteins. FEOJ induced the p38 MAPK signaling pathway, playing at least in part an important role in FEOJ-induced apoptosis. This study suggested that FEOJ may induce caspase-dependent apoptosis in human leukemic cells by regulating MMP (ΔΨm) through suppressing Bcl-2 and X-IAP. In addition, the results indicated that upstream p38 MAPK signaling regulates the apoptotic effect of FEOJ. This study provides evidence that FEOJ might have anti-cancer potential for human leukemic cells.

20(S)-Ginsenoside Rh2 Induce the Apoptosis and Autophagy in U937 and K562 Cells.

PubMed

Zhuang, Jianjian; Yin, Juxin; Xu, Chaojian; Mu, Ying; Lv, Shaowu

2018-03-08

Acute myeloid leukemia (AML) and Chronic myelogenous leukemia (CML) are common leukemia in adults. 20(S)-GRh2 is an important bioactive substance that is present in Panax ginseng. However, there are no investigations that deal with the comparison of apoptosis, the occurrence of autophagy, and the relationship between apoptosis and autophagy after being treated with 20(S)-GRh2 in AML and CML. In this study, we explored the effect of 20(S)-GRh2 on the AML and CML (U937 and K562). Fluorescence microscopy, CCK-8, Quantitative realtime PCR, Western blot, transmission electron microscopy (TEM), and flow cytometric analysis were used to detect the occurrence of cell proliferation inhibition, apoptosis, and autophagy. By using the above methods, it was determined that apoptosis induced by 20(S)-GRh2 was more obvious in K562 than U937 cells and 20(S)-GRh2 could generate autophagy in K562 and U937 cells. When pretreated by a specific inhibitor of autophagy, (3-methyladenine), the 20(S)-GRh2-induced apoptosis was enhanced, which indicated that 20(S)-GRh2-induced autophagy may protect U937 and K562 cells from undergoing apoptotic cell death. On the other hand, pretreated by an apoptosis suppressor (Z-VAD-FMK), it greatly induced the autophagy and partially prevented 20(S)-GRh2 induced apoptosis. This phenomenon indicated that 20(S)-GRh2-induced autophagy may serve as a survival mechanism and apoptosis and autophagy could act as partners to induce cell death in a cooperative manner. These findings may provide a rationale for future clinical application by using 20(S)-GRh2 combined autophagy inhibitors for AML and CML.

Suppression of Akt/Foxp3-mediated miR-183 expression blocks Sp1-mediated ADAM17 expression and TNFα-mediated NFκB activation in piceatannol-treated human leukemia U937 cells.

PubMed

Liu, Wen-Hsin; Chang, Long-Sen

2012-09-01

To address the mechanism of piceatannol in inhibiting TNFα-mediated pathway, studies on piceatannol-treated human leukemia U937 cells were conducted. Piceatannol treatment reduced TNFα shedding and NFκB activation and decreased the release of soluble TNFα into the culture medium of U937 cells. Moreover, ADAM17 expression was down-regulated in piceatannol-treated cells. Over-expression of ADAM17 abrogated the ability of piceatannol to suppress TNFα-mediated NFκB activation. Piceatannol-evoked β-TrCP up-regulation promoted Sp1 degradation, thus reducing transcriptional level of ADAM17 gene in U937 cells. Piceatannol treatment induced p38 MAPK phosphorylation but inactivation of Akt and ERK. In contrast to p38 MAPK inhibitor or restoration of ERK activation, transfection of constitutive active Akt abolished the effect of piceatannol on β-TrCP, Sp1 and ADAM17 expression. Piceatannol-elicited down-regulation of miR-183 expression was found to cause β-TrCP up-regulation. Inactivation of Akt resulted in Foxp3 down-regulation and reduced miR-183 expression in piceatannol-treated cells. Knock-down of Foxp3 and chromatin immunoprecipitating revealed that Foxp3 genetically regulated transcription of miR-183 gene. Taken together, our data indicate that suppression of Akt/Foxp3-mediated miR-183 expression blocks Sp1-mediated ADAM17 expression in piceatannol-treated U937 cells. Consequently, piceatannol suppresses TNFα shedding, leading to inhibition of TNFα/NFκB pathway. Copyright © 2012 Elsevier Inc. All rights reserved.

In vitro immunotoxicity assessment of culture-derived extracellular vesicles in human monocytes

PubMed Central

Rosas, Lucia E.; Elgamal, Ola A.; Mo, Xiaokui; Phelps, Mitch A.; Schmittgen, Thomas D.; Papenfuss, Tracey L.

2016-01-01

The potential to engineer extracellular vesicles (EV) that target specific cells and deliver a therapeutic payload has propelled a growing interest in their development as promising therapeutics. These EV are often produced from cultured cells. Very little is known about the interaction of cell culture-derived EV with cells of the immune system and their potential immunomodulatory effects. The present study evaluated potential immunotoxic effects of HEK293T-derived EV on the human monocytic cell lines THP-1 and U937. Incubation of cells with different doses of EV for 16–24 h was followed by assessment of cytotoxicity and cell function by flow cytometry. Changes in cell functionality were evaluated by the capacity of cells to phagocytize fluorescent microspheres. In addition, the internalization of labeled EV in THP-1 and U937 cells was evaluated. Exposure to EV did not affect the viability of THP-1 or U937 cells. Although lower doses of the EV increased phagocytic capacity in both cell lines, phagocytic efficiency of individual cells was not affected by EV exposure at any of the doses evaluated. This study also demonstrated that THP-1 and U937 monocytic cells are highly permissive to EV entry in a dose-response manner. These results suggest that, although HEK293T-derived EV are efficiently internalized by human monocytic cells, they do not exert a cytotoxic effect or alter phagocytic efficiency on the cell lines evaluated. PMID:27075513

Curcumin induces apoptosis in human leukemic cell lines through an IFIT2-dependent pathway

PubMed Central

Zhang, Yonglu; Kong, Yunyuan; Liu, Shuyuan; Zeng, Lingbing; Wan, Lagen; Zhang, Zhanglin

2017-01-01

ABSTRACT Curcumin, the primary bioactive component isolated from turmeric, has been shown to possess variety of biologic functions including anti-cancer activity. However, molecular mechanisms in different cancer cells are various. In the present study, we demonstrated that curcumin induced G2/M cell cycle arrest and apoptosis by increasing the expression levels of cleaved caspase-3, cleaved PARP and decreasing the expression of BCL−2 in U937 human leukemic cells but not in K562 cells. We found some interferon induced genes, especially interferon-induced protein with tetratricopeptide repeats 2 (IFIT2), were significantly upregulated when treated with curcumin in U937 cells by gene expression chip array, and further confirmed that the expression of IFIT2 was obviously higher in U937 than that in K562 cells by Western blot assay. In addition, inhibiting the expression of IFIT2 by shRNA in U937 rescued curcumin-induced apoptosis and exogenous overexpression of IFIT2 by lentiviral transduction or treating with IFNγ in K562 cells enhanced anti-cancer activity of curcumin. These results indicated for the first time that curcumin induced leukemic cell apoptosis via an IFIT2-dependent signaling pathways. The present study identified a novel mechanism underlying the antitumor effects of curcumin, and may provide a theoretical basis for curcumin combined with interferon in the cancer therapeutics. PMID:28071969

Tunicamycin promotes apoptosis in leukemia cells through ROS generation and downregulation of survivin expression.

PubMed

Lim, Eun Jin; Heo, Jeonghoon; Kim, Young-Ho

2015-08-01

Tunicamycin (TN), one of the endoplasmic reticulum stress inducers, has been reported to inhibit tumor cell growth and exhibit anticarcinogenic activity. However, the mechanism by which TN initiates apoptosis remains poorly understood. In the present study, we investigated the effect of TN on the apoptotic pathway in U937 cells. We show that TN induces apoptosis in association with caspase-3 activation, generation of reactive oxygen species (ROS), and downregulation of survivin expression. P38 MAPK (mitogen-activated protein kinase) and the generation of ROS signaling pathway play crucial roles in TN-induced apoptosis in U937 cells. We hypothesized that TN-induced activation of p38 MAPK signaling pathway is responsible for cell death. To test this hypothesis, we selectively inhibited MAPK during treatment with TN. Our data demonstrated that inhibitor of p38 (SB), but not ERK (PD) or JNK (SP), partially maintained apoptosis during treatment with TN. Pre-treatment with NAC and GSH markedly prevented cell death, suggesting a role for ROS in this process. Ectopic expression of survivin in U937 cells attenuated TN-induced apoptosis by suppression of caspase-3 cleavage, mitochondrial membrane potential, and cytochrome c release in U937 cells. Taken together, our results show that TN modulates multiple components of the apoptotic response of human leukemia cells and raise the possibility of a novel therapeutic strategy for hematological malignancies.

CRISPR/Cas9-mediated ASXL1 mutations in U937 cells disrupt myeloid differentiation

PubMed Central

Wu, Zhi-Jie; Zhao, Xin; Banaszak, Lauren G.; Gutierrez-Rodrigues, Fernanda; Keyvanfar, Keyvan; Gao, Shou-Guo; Raffo, Diego Quinones; Kajigaya, Sachiko; Young, Neal S.

2018-01-01

Additional sex combs-like 1 (ASXL1) is a well-known tumor suppressor gene and epigenetic modifier. ASXL1 mutations are frequent in myeloid malignances; these mutations are risk factors for the development of myelodysplasia and also appear as small clones during normal aging. ASXL1 appears to act as an epigenetic regulator of cell survival and myeloid differentiation; however, the molecular mechanisms underlying the malignant transformation of cells with ASXL1 mutations are not well defined. Using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein-9 nuclease (Cas9) genome editing, heterozygous and homozygous ASXL1 mutations were introduced into human U937 leukemic cells. Comparable cell growth and cell cycle progression were observed between wild-type (WT) and ASXL1-mutated U937 cells. Drug-induced cytotoxicity, as measured by growth inhibition and apoptosis in the presence of the cell-cycle active agent 5-fluorouracil, was variable among the mutated clones but was not significantly different from WT cells. In addition, ASXL1-mutated cells exhibited defects in monocyte/macrophage differentiation. Transcriptome analysis revealed that ASXL1 mutations altered differentiation of U937 cells by disturbing genes involved in myeloid differentiation, including cytochrome B-245 β chain and C-type lectin domain family 5, member A. Dysregulation of numerous gene sets associated with cell death and survival were also observed in ASXL1-mutated cells. These data provide evidence regarding the underlying molecular mechanisms induced by mutated ASXL1 in leukemogenesis. PMID:29532865

Identification of 6-methylsulfinylhexyl isothiocyanate as an apoptosis-inducing component in wasabi.

PubMed

Watanabe, Makoto; Ohata, Masahiko; Hayakawa, Sumio; Isemura, Mamoru; Kumazawa, Shigenori; Nakayama, Tsutomu; Furugori, Michiyo; Kinae, Naohide

2003-03-01

The ethanol extract from Japanese horseradish wasabi was found to inhibit cell proliferation in human monoblastic leukemia U937 cells by inducing apoptotic cell death. Separation by methods including silica gel chromatography and preparative HPLC gave an active compound, which was identified as 6-methylsulfinylhexyl isothiocyanate (6-HITC). Several lines of evidence indicated that 6-HITC induced apoptosis in U937 cells and human stomach cancer MKN45 cells. Thus, 6-HITC is potentially useful as a natural anti-cancer agent.

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

NASA Astrophysics Data System (ADS)

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.

Cytotoxic and HIV-1 enzyme inhibitory activities of Red Sea marine organisms.

PubMed

Ellithey, Mona S; Lall, Namrita; Hussein, Ahmed A; Meyer, Debra

2014-02-25

Cancer and HIV/AIDS are two of the greatest public health and humanitarian challenges facing the world today. Infection with HIV not only weakens the immune system leading to AIDS and increasing the risk of opportunistic infections, but also increases the risk of several types of cancer. The enormous biodiversity of marine habitats is mirrored by the molecular diversity of secondary metabolites found in marine animals, plants and microbes which is why this work was designed to assess the anti-HIV and cytotoxic activities of some marine organisms of the Red Sea. The lipophilic fractions of methanolic extracts of thirteen marine organisms collected from the Red Sea (Egypt) were screened for cytotoxicity against two human cancer cell lines; leukaemia (U937) and cervical cancer (HeLa) cells. African green monkey kidney cells (Vero) were used as normal non-malignant control cells. The extracts were also tested for their inhibitory activity against HIV-1 enzymes, reverse transcriptase (RT) and protease (PR). Cytotoxicity results showed strong activity of the Cnidarian Litophyton arboreum against U-937 (IC50; 6.5 μg/ml ±2.3) with a selectivity index (SI) of 6.45, while the Cnidarian Sarcophyton trochliophorum showed strong activity against HeLa cells (IC50; 5.2 μg/ml ±1.2) with an SI of 2.09. Other species showed moderate to weak cytotoxicity against both cell lines. Two extracts showed potent inhibitory activity against HIV-1 protease; these were the Cnidarian jelly fish Cassiopia andromeda (IC50; 0.84 μg/ml ±0.05) and the red algae Galaxura filamentosa (2.6 μg/ml ±1.29). It is interesting to note that the most active extracts against HIV-1 PR, C. andromeda and G. filamentosa showed no cytotoxicity in the three cell lines at the highest concentration tested (100 μg/ml). The strong cytotoxicity of the soft corals L. arboreum and S. trochliophorum as well as the anti-PR activity of the jelly fish C. andromeda and the red algae G. filamentosa suggests the medicinal potential of crude extracts of these marine organisms.

Cytotoxic and HIV-1 enzyme inhibitory activities of Red Sea marine organisms

PubMed Central

2014-01-01

Background Cancer and HIV/AIDS are two of the greatest public health and humanitarian challenges facing the world today. Infection with HIV not only weakens the immune system leading to AIDS and increasing the risk of opportunistic infections, but also increases the risk of several types of cancer. The enormous biodiversity of marine habitats is mirrored by the molecular diversity of secondary metabolites found in marine animals, plants and microbes which is why this work was designed to assess the anti-HIV and cytotoxic activities of some marine organisms of the Red Sea. Methods The lipophilic fractions of methanolic extracts of thirteen marine organisms collected from the Red Sea (Egypt) were screened for cytotoxicity against two human cancer cell lines; leukaemia (U937) and cervical cancer (HeLa) cells. African green monkey kidney cells (Vero) were used as normal non-malignant control cells. The extracts were also tested for their inhibitory activity against HIV-1 enzymes, reverse transcriptase (RT) and protease (PR). Results Cytotoxicity results showed strong activity of the Cnidarian Litophyton arboreum against U-937 (IC50; 6.5 μg/ml ±2.3) with a selectivity index (SI) of 6.45, while the Cnidarian Sarcophyton trochliophorum showed strong activity against HeLa cells (IC50; 5.2 μg/ml ±1.2) with an SI of 2.09. Other species showed moderate to weak cytotoxicity against both cell lines. Two extracts showed potent inhibitory activity against HIV-1 protease; these were the Cnidarian jelly fish Cassiopia andromeda (IC50; 0.84 μg/ml ±0.05) and the red algae Galaxura filamentosa (2.6 μg/ml ±1.29). It is interesting to note that the most active extracts against HIV-1 PR, C. andromeda and G. filamentosa showed no cytotoxicity in the three cell lines at the highest concentration tested (100 μg/ml). Conclusion The strong cytotoxicity of the soft corals L. arboreum and S. trochliophorum as well as the anti-PR activity of the jelly fish C. andromeda and the red algae G. filamentosa suggests the medicinal potential of crude extracts of these marine organisms. PMID:24568567

AML sensitivity to YM155 is modulated through AKT and Mcl-1

PubMed Central

de Necochea-Campion, Rosalia; Diaz Osterman, Carlos J.; Hsu, Heng-Wei; Fan, Junjie; Mirshahidi, Saied; Wall, Nathan R.; Chen, Chien-Shing

2015-01-01

HL60 and U937 (acute myeloid leukemia (AML) cell lines) were assessed for sensitivity to YM155, and found to have distinct sensitive and resistant phenotypes, respectively. In HL60 cells, YM155 inhibition of growth proliferation was due to apoptosis which was measured by annexin V/PI staining. YM155 induced apoptosis through activation of intrinsic and extrinsic pathways that also culminated in caspase-3 activity and PARP cleavage. YM155 sensitivity was partially associated with this compound’s ability to downregulate survivin transcription since this was more pronounced in the HL60 cell line. However, marked differences were also observed in XIAP, Bcl-2, and Mcl-1L, and Mcl-1s. Furthermore, YM155 treatment completely inhibited production of total Akt protein in HL60, but not U937 cells. Importantly, Akt activity (pAkt-Ser473) levels were maintained in YM155 treated U937 cells which may help stabilize other anti-apoptotic proteins. Combination treatments with an Akt inhibitor, MK-2206, reduced levels of pAkt-Ser473 in U937 cells and synergistically sensitized them to YM155 cytotoxicity. Collectively our results indicate that Akt signaling may be an important factor mediating YM155 response in AML, and combinatorial therapies with Akt inhibitors could improve treatment efficacy in YM155-resistant cells. PMID:26118775

Induction of Apoptosis in U937 Cells by Using a Combination of Bortezomib and Low-Intensity Ultrasound

PubMed Central

Saliev, Timur; Feril, Loreto B.; Ogawa, Koichi; Watanabe, Akiko; Begimbetova, Dinara; Molkenov, Askhat; Alimbetov, Dauren; Tachibana, Katsuro

2016-01-01

Background We scrutinized the feasibility of apoptosis induction in blood cancer cells by means of low-intensity ultrasound and the proteasome inhibitor bortezomib (Velcade). Material/Methods Human leukemic monocyte lymphoma U937 cells were subjected to ultrasound in the presence of bortezomib and the echo contrast agent Sonazoid. Two types of acoustic intensity (0.18 W/cm2 and 0.05 W/cm2) were used for the experiments. Treated U937 cells were analyzed for viability and levels of early and late apoptosis. In addition, scanning electron microscopy analysis of treated cells was performed. Results The percentage of cells that underwent early apoptosis in the group treated with ultrasound and Sonazoid was 8.0±1.31% (intensity 0.18 W/cm2) and 7.0±1.69% (0.05 W/cm2). However, coupling of bortezomib and Sonazoid resulted in an increase in the percentage of cells in the early apoptosis phase, up to 32.50±3.59% (intensity 0.18 W/cm2) and 33.0±4.90% (0.05 W/cm2). The percentage of U937 cells in the late apoptosis stage was not significantly different from that in the group treated with bortezomib only. Conclusions Our findings indicate the feasibility of apoptosis induction in blood cancer cells by using a combination of bortezomib, ultrasound contrast agents, and low-intensity ultrasound. PMID:28003640

[Molecular mechanism involved in adhesion of monocytes to endothelial cells induced by nicotine and Porphyromonas gingivalis-LPS].

PubMed

Wang, Yi-xiang; An, Na; Ouyang, Xiang-ying

2015-10-18

To investigate molecular mechanism involved in nicotine in combination with Porphyromonas gingivalis (P.g) caused monocyte-endothelial cell adhesion. The effect of nicotine, P.g-lipopolysaccharide (P.g-LPS) and their combination on the proliferation of U937 cells was determined by CCK-8 method. Interleukin-6 (IL-6) expression was investigated by real-time PCR after U937 cells were treated with nicotine, P.g-LPS and their combination. In human umbilical vein endothelial cells (HUVECs), the expressions of monocyte chemoattractant protein CCL-8 and adhesion molecules including vascular cell adhesion molecule 1 (Vcam-1), very late antigen 4 alpha (VLA4α), tumor necrosis factor receptor superfamily member 4 (OX40) and OX40 ligand (OX40L) were detected by real-time PCR or Western blotting assays after HUVEC cells were treated with nicotine, P.g-LPS and their combination. Adhesion of monocytes to endothelial cells was detected after the HUVECs and U937 cells were stimulated with nicotine, P.g-LPS and their combination, respectively. P.g-LPS did not affect the proliferative ability of nicotine in U937 cells. However, the ability of P.g-LPS induced IL-6 expression was inhibited by 100 μmol/L nicotine in U937 cells. In HUVECs, the expressions of CCL-8, Vcam-1, VLA4α, OX40 and OX40L were significantly up-regulated by nicotine and P.g-LPS combination compared with nicotine alone, P.g-LPS alone and the untreated control. Adhesion of monocytes to HUVECs results showed that the two types of cells treated with nicotine in combination with P.g-LPS could markedly increase the adhesion ability of monocytes to HUVECs. P.g-LPS in combination with nicotine could recruit monocytes to endothelial lesion through up-regulation of CCL-8, and promote adhesion of monocytes to endothelial cells through enhancement of Vcam-1/VLA4α and OX40/OX40L interactions, which could be involved in the initiation and development of atherosclerosis.

Cucurbitacin E as a new inhibitor of cofilin phosphorylation in human leukemia U937 cells.

PubMed

Nakashima, Souichi; Matsuda, Hisashi; Kurume, Ai; Oda, Yoshimi; Nakamura, Seikou; Yamashita, Masayuki; Yoshikawa, Masayuki

2010-05-01

Cucurbitane-type triterpenes, cucurbitacins B and E, were reported to exhibit cytotoxic effects in several cell lines mediated by JAK/STAT3 signaling. However, neither compound inhibited phosphorylation of STAT3 in human leukemia (U937) cells at low concentrations. We therefore synthesized a biotin-linked cucurbitacin E to isolate target proteins based on affinity for the molecule. As a result, cofilin, which regulates the depolymerization of actin, was isolated and suggested to be a target. Cucurbitacins E and I inhibited the phosphorylation of cofilin in a concentration-dependent manner, and their effective concentrations having the same range as the concentrations at which they had cytotoxic effects in U937 cells. In addition, the fibrous-/globular-actin ratio was decreased after treatment with cucurbitacin E in HT1080 cells. These findings suggested that the inhibition of cofilin's phosphorylation increased the severing activity of cofilin, and then the depolymerization of actin was enhanced after treatment with cucurbitacin E at lower concentrations. 2010 Elsevier Ltd. All rights reserved.

Inhibition of X-linked inhibitor of apoptosis protein enhances anti-tumor potency of pure total flavonoids on the growth of leukemic cells

PubMed Central

Wu, Liqiang; Zhang, Xiuxia; Lin, Xiaojie; Wang, Bo; Huang, Chang; Qin, Yao; Lin, Shengyun

2018-01-01

Flavonoids, a vast group of polyphenols widely distributed in plants, are known to possess a range of biological activities and potential anti-tumor effects. X-linked inhibitor of apoptosis protein (XIAP) promotes the progression of leukemia by preventing tumor cells undergoing apoptosis. The present study investigated the potential effects and underlying mechanisms of pure total flavonoids from Citrus paradisi Macfad (PTFC) on human U937 cells, and explored the effects of short hairpin (sh)RNA-mediated XIAP knockdown on the anti-cancer effects of PTFC. Western blotting was used to determine level of apoptosis-associated effectors following PTFC treatment. A lentiviral vector of RNA interference of XIAP gene was constructed to downregulate XIAP expression. MTT assay and flow cytometry were used to determine the effects of PTFC separately or combined with XIAP-shRNA on inhibition and apoptosis of U937 cells, respectively. Treatment with PTFC effectively inhibited leukemic cell proliferation in a dose- and time-dependent manner. PTFC induced apoptosis of U937 cells in a dose-dependent manner, at a particular concentration range, by decreasing XIAP expression levels and activating caspases-3, −7 and −9. PTFC treatment combined with XIAP-shRNA additionally demonstrated a marked increase in cell apoptosis, compared with PTFC or XIAP-shRNA alone (P<0.05). Therefore, these findings suggest that PTFC inhibits growth and induces apoptosis in U937 cells in vitro. Furthermore, suppression of XIAP expression enhances these effects. PMID:29434799

Effects of the ACTH(4-9) analogue, ORG 2766, on vincristine cytotoxicity in two human lymphoma cell lines, U937 and U715.

PubMed Central

Kiburg, B.; van de Loosdrecht, A. A.; Schweitzer, K. M.; Ossenkoppele, G. J.; Müller, L. J.; Heimans, J. J.; Huijgens, P. C.

1994-01-01

The use of cytotoxic drug vincristine (VCR) is limited by the occurrence of peripheral neuropathy. A neurotrophic ACTH(4-9) analogue, ORG 2766, is being studied for its protective effect. Possible modulatory effects of ORG 2766 on tumour cell growth and interference with the cytotoxic efficacy of VCR were studied in two human lymphoma cell lines, U937 and U715. The effects of ORG 2766 on cell growth and survival and on VCR-mediated cytotoxicity were investigated using two MTT-based assays to study direct cytotoxic effects and to assess residual growth after pretreatment. Treatment with ORG 2766 alone had no effect on cell growth and survival. Neither did this drug affect VCR cytotoxicity. However, after 96 h pretreatment with ORG 2766 and a culture period of 7 days, a reduction in residual growth and a potentiation of VCR-induced inhibition of growth capacity was observed in U715 cells, and to some extent also in U937 cells. It is concluded that ORG 2766 has no stimulatory effects on tumour growth and does not negatively interfere with VCR-mediated cytotoxicity. Rather it enhances the cytostatic effect of VCR. It is suggested that ORG 2766 can safely be used in clinical trials investigating the ability of ORG 2766 to counteract VCR-induced neurotoxicity. PMID:8123480

[Influence of macrophages on the expression of vascular endothelial growth factor receptor mRNA, homeobox B2 mRNA, and integrin alpha nu beta3 in vascular endothelial strain].

PubMed

Liu, Liang; Liu, Chang; Zhang, Xiao-qi; Ming, Jia; Liu, Xu-sheng; Xu, Hui; Cheng, Tian-min

2005-06-01

To investigate the influence of macrophages on the expression of the vascular endothelial growth factor (VEGF) receptor (KDR) mRNA, homeobox B2 (HOXB2) mRNA, and integrin alpha nu beta3 in vitro in vascular endothelial strain. Human umbilical vein cells (ECV304) were cultured in vitro and divided into 4 groups, i.e. (1) ECV304 group, (2) ECV304 + conA group [with conA (25 microg/ml in culture) added to ECV304], (3) ECV304 + U937 group (with 1 x 10(5)/ml of U937 cells added to 1 x 10(5)/ml ECV 304), (4) ECV304 + U937 + conA group [with 1 x 10(5)/ml of U937 cells and conA (25 microg/ml in culture)] groups. Forty-eight hours after culturing, the expression of integrin receptor alpha nu beta3 and the changes in the expression of KDR mRNA and HOXB2 mRNA in each group were determined by immunofluorescent technique and RT-PCR, respectively. The expression of integrin receptor alpha nu beta3, KDR mRNA, and HOXB2 mRNA in ECV304 group were 6.7 +/- 1.5, 0.633 +/- 0.012, and 0.674 +/- 0.004, respectively, while those in ECV304 + U937 + conA group (10.2 +/- 1.7, 0.879 +/- 0.003, 0.947 +/- 0.003) were obviously more upregulated when compared with those in ECV304 group (P < 0.01). No difference in the above indices was found between ECV304 and ECV304 + conA, ECV304 + U937 groups (P > 0.05). Macrophages activated by ConA can accelerate the proliferation, migration and adhesion to the basement membrane matrix of vascular endothelial cells through the influence on the expression of KDR mRNA, HOXB2 mRNA and integrin alpha nu beta3, and through this pathway the angiogenesis is modulated.

Homoharringtonine targets Smad3 and TGF-β pathway to inhibit the proliferation of acute myeloid leukemia cells.

PubMed

Chen, Jian; Mu, Qitian; Li, Xia; Yin, Xiufeng; Yu, Mengxia; Jin, Jing; Li, Chenying; Zhou, Yile; Zhou, Jiani; Suo, Shanshan; Lu, Demin; Jin, Jie

2017-06-20

Homoharringtonine (HHT) has long and widely been used in China for the treatment of acute myeloid leukemia (AML), the clinical therapeutic effect is significant but the working mechanism is poorly understood. The purpose of this study is to screen the possible target for HHT with virtual screening and verify the findings by cell experiments. Software including Autodock, Python, and MGL tools were used, with HHT being the ligand and proteins from PI3K-Akt pathway, Jak-stat pathway, TGF-β pathway and NK-κB pathway as the receptors. Human AML cell lines including U937, KG-1, THP-1 were cultured and used as the experiment cell lines. MTT assay was used for proliferation detection, flowcytometry was used to detect apoptosis and cell cycle arrest upon HHT functioning, western blotting was used to detect the protein level changes, viral shRNA transfection was used to suppress the expression level of the target protein candidate, and viral mRNA transfection was used for over-expression. Virtual screening revealed that smad3 from TGF-β pathway might be the candidate for HHT binding. In AML cell line U937 and KG-1, HHT can induce the Ser423/425 phosphorylation of smad3, and this phosphorylation can subsequently activate the TGF-β pathway, causing cell cycle arrest at G1 phase in U937 cells and apoptosis in KG-1 cells, knockdown of smad3 can impair the sensitivity of U937 cell to HHT, and over-expression of smad3 can re-establish the sensitivity in both cell lines. We conclude that smad3 is the probable target protein of HHT and plays an important role in the functioning mechanism of HHT.

Homoharringtonine targets Smad3 and TGF-β pathway to inhibit the proliferation of acute myeloid leukemia cells

PubMed Central

Yin, Xiufeng; Yu, Mengxia; Jin, Jing; Li, Chenying; Zhou, Yile; Zhou, Jiani; Suo, Shanshan; Lu, Demin; Jin, Jie

2017-01-01

Homoharringtonine (HHT) has long and widely been used in China for the treatment of acute myeloid leukemia (AML), the clinical therapeutic effect is significant but the working mechanism is poorly understood. The purpose of this study is to screen the possible target for HHT with virtual screening and verify the findings by cell experiments. Software including Autodock, Python, and MGL tools were used, with HHT being the ligand and proteins from PI3K-Akt pathway, Jak-stat pathway, TGF-β pathway and NK-κB pathway as the receptors. Human AML cell lines including U937, KG-1, THP-1 were cultured and used as the experiment cell lines. MTT assay was used for proliferation detection, flowcytometry was used to detect apoptosis and cell cycle arrest upon HHT functioning, western blotting was used to detect the protein level changes, viral shRNA transfection was used to suppress the expression level of the target protein candidate, and viral mRNA transfection was used for over-expression. Virtual screening revealed that smad3 from TGF-β pathway might be the candidate for HHT binding. In AML cell line U937 and KG-1, HHT can induce the Ser423/425 phosphorylation of smad3, and this phosphorylation can subsequently activate the TGF-β pathway, causing cell cycle arrest at G1 phase in U937 cells and apoptosis in KG-1 cells, knockdown of smad3 can impair the sensitivity of U937 cell to HHT, and over-expression of smad3 can re-establish the sensitivity in both cell lines. We conclude that smad3 is the probable target protein of HHT and plays an important role in the functioning mechanism of HHT. PMID:28454099

Hematopoietic Cancer Cell Lines Can Support Replication of Sabin Poliovirus Type 1

PubMed Central

van Eikenhorst, Gerco; de Gruijl, Tanja D.; van der Pol, Leo A.; Bakker, Wilfried A. M.

2015-01-01

Viral vaccines can be produced in adherent or in suspension cells. The objective of this work was to screen human suspension cell lines for the capacity to support viral replication. As the first step, it was investigated whether poliovirus can replicate in such cell lines. Sabin poliovirus type 1 was serially passaged on five human cell lines, HL60, K562, KG1, THP-1, and U937. Sabin type 1 was capable of efficiently replicating in three cell lines (K562, KG1, and U937), yielding high viral titers after replication. Expression of CD155, the poliovirus receptor, did not explain susceptibility to replication, since all cell lines expressed CD155. Furthermore, we showed that passaged virus replicated more efficiently than parental virus in KG1 cells, yielding higher virus titers in the supernatant early after infection. Infection of cell lines at an MOI of 0.01 resulted in high viral titers in the supernatant at day 4. Infection of K562 with passaged Sabin type 1 in a bioreactor system yielded high viral titers in the supernatant. Altogether, these data suggest that K562, KG1, and U937 cell lines are useful for propagation of poliovirus. PMID:25815312

The inhibition of macrophage foam cell formation by tetrahydroxystilbene glucoside is driven by suppressing vimentin cytoskeleton.

PubMed

Yao, Wenjuan; Huang, Lei; Sun, Qinju; Yang, Lifeng; Tang, Lian; Meng, Guoliang; Xu, Xiaole; Zhang, Wei

2016-10-01

Macrophage foam cell formation triggered by oxLDL is an important event that occurs during the development of atherosclerosis. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-glucoside (TSG) exhibits significant anti-atherosclerotic activity. Herein we used U937 cells induced by PMA and oxLDL in vitro to investigate the inhibitory effects of TSG on U937 differentiation and macrophage foam cell formation. TSG pretreatment markedly inhibited cell differentiation induced by PMA, macrophage apoptosis and foam cell formation induced by oxLDL. The inhibition of vimentin expression and cleavage was involved in these inhibitory effects of TSG. The suppression of vimentin by siRNA in U937 significantly inhibited cell differentiation, apoptosis and foam cell formation. Using inhibitors for TGFβR1 and PI3K, we found that vimentin production in U937 cells is regulated by TGFβ/Smad signaling, but not by PI3K-Akt-mTOR signaling. Meanwhile, TSG pretreatment inhibited both the expression of TGFβ1 and the phosphorylation of Smad2 and Smad3, and TSG suppressed the nuclear translocation of Smad4 induced by PMA and oxLDL. Furthermore, TSG attenuated the induced caspase-3 activation and adhesion molecules levels by PMA and oxLDL. PMA and oxLDL increased the co-localization of vimentin with ICAM-1, which was attenuated by pretreatment with TSG. These results suggest that TSG inhibits macrophage foam cell formation through suppressing vimentin expression and cleavage, adhesion molecules expression and vimentin-ICAM-1 co-localization. The interruption of TGFβ/Smad pathway and caspase-3 activation is responsible for the downregulation of TSG on vimentin expression and degradation, respectively. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Assessment of the U937 cell line for the detection of contact allergens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Python, Francois; Goebel, Carsten; Aeby, Pierre

2007-04-15

The human myeloid cell line U937 was evaluated as an in vitro test system to identify contact sensitizers in order to develop alternatives to animal tests for the cosmetic industry. Specific culture conditions (i.e., presence of interleukin-4, IL-4) were applied to obtain a dendritic cell-like phenotype. In the described test protocol, these cells were exposed to test chemicals and then analyzed by flow cytometry for CD86 expression and by quantitative real-time reverse transcriptase-polymerase chain reaction for IL-1{beta} and IL-8 gene expressions. Eight sensitizers, three non-sensitizers and five oxidative hair dye precursors were examined after 24-, 48- and 72-h exposure times.more » Test item-specific modulations of the chosen activation markers (CD86, IL-1{beta} and IL-8) suggest that this U937 activation test could discriminate test items classified as contact sensitizers or non-sensitizers in the local lymph node assay in mice (LLNA). More specifically, a test item can be considered as a potential sensitizer when it significantly induced the upregulation of the expression of at least two markers. Using this approach, we could correctly evaluate the dendritic cell (DC) activation potential for 15 out of 16 tested chemicals. We conclude that the U937 activation test may represent an useful tool in a future in vitro test battery for predicting sensitizing properties of chemicals.« less

Effects of selected food phytochemicals in reducing the toxic actions of TCDD and p,p′-DDT in U937 macrophages

PubMed Central

Sciullo, Eric M.; Vogel, Christoph F.; Wu, Dalei; Murakami, Akira; Ohigashi, Hajime

2010-01-01

To assess the effectiveness of selected food phytochemicals in reducing the toxic effects of the environmental toxicants, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and p,p′-DDT (DDT), we tested the potencies of auraptene, nobiletin, zerumbone, and (±)-13-hydroxy-10-oxo-trans-11-octadecenoic acid (13-HOA) in reversing the inflammatory action of these toxicants in U937 human macrophages. Using quantitative RT–PCR as the initial screening assay, we identified antagonistic actions of zerumbone and auraptene against the action of TCDD and DDT in up-regulating the mRNA expressions of COX-2 and VEGF. The functional significance of the inhibitory action of zerumbone on COX-2 expression was confirmed by demonstrating its suppression of TCDD-induced activation of COX-2 gene expression in mouse MMDD1 cells. We tested auraptene on DDT-induced reactive oxygen species (ROS) formation in U937 macrophages and found that auraptene is a powerful agent antagonizing this action of DDT. To confirm the significance of these actions of zerumbone and auraptene at the cellular level, we assessed their influence on TCDD-induced apoptosis resistance in intact U937 macrophages and found that they are capable of reversing this action of TCDD. In conclusion, zerumbone and auraptene were identified to be the most effective agents in protecting U937 macrophages from developing these cell toxic effects of TCDD and DDT. PMID:20865247

Involvement of PKC and ROS in the cytotoxic mechanism of anti-leukemic decursin and its derivatives and their structure-activity relationship in human K562 erythroleukemia and U937 myeloleukemia cells.

PubMed

Kim, Hyeon Ho; Sik Bang, Sung; Seok Choi, Jin; Han, Hogyu; Kim, Ik-Hwan

2005-06-08

Protein kinase C (PKC) plays an important role in the proliferation and differentiation of various cell types including normal and leukemic hematopoietic cells. Recently, various PKC modulators were used as a chemotherapeutic agent of leukemia. Decursin (1), a pyranocoumarin from Angelica gigas, exhibits the cytotoxic effects on various human cancer cell lines and in vitro PKC activation. For the development of more effective anticancer agents with PKC modulation activity, 11 decursin derivatives 2-12 were chemically synthesized and evaluated for their ability to act as a tumor-suppressing PKC activator and as an antagonist to phorbol 12-myristate 13-acetate (PMA), a tumor-promoting PKC activator. In the presence of phosphatidylserine (PS), all of 12 compounds 1-12 activated PKC (mainly alpha, beta, and gamma isozymes) but only three compounds 1-3 activated PKC even in the absence of PS. Six compounds 1-6 containing the coumarin structure were cytotoxic to human K562 erythroleukemia and U937 myeloleukemia cells. A cytotoxic mechanism of decursin and its derivatives was investigated using TUR cells, a PKC betaII-deficient variant of U937 cells. Among six compounds 1-6 with cytotoxicity to K562 and U937 leukemia cells, only three compounds 1-3 were cytotoxic to TUR cells. Therefore, compounds 1-3 and 4-6 inhibit the proliferation of leukemia cells in a PKC betaII-independent and dependent manner, respectively, indicating that the side chain of compounds determines the dependency of their cytotoxicity on PKC betaII. To further elucidate the cytotoxic mechanism of compounds 1 and 2, levels of PKC isozymes and generation of reactive oxygen species (ROS) were investigated. Compounds 1-2 induced the down-regulation of PKC alpha and betaII in K562 cells and the production of ROS in U937 cells. Thus, PKC and ROS are probably important factors in the cytotoxic mechanism of compounds 1-2. From these results, the structure-activity relationship of decursin and its derivatives is as follows: (i) the coumarin structure is required for anti-leukemic activity and (ii) the side chain is a determinant of PKC activation and the cytotoxic mechanism in leukemia cells.

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

PubMed

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.

Bone marrow - mesenchymal stem cells impact on the U937 cells in the presence of staphylococcal enterotoxin B (SEB).

PubMed

Ejtehadifar, Mostafa; Halabian, Raheleh; Ghazavi, Ali; Khansarinejad, Behzad; Mosayebi, Ghasem; Imani Fooladi, Abbas Ali

2018-04-14

The growing resistance against conventional chemotherapy in acute myeloid leukemia (AML) is a noticeable clinical concern. Therefore, many researchers are looking for novel substances to overcome drug resistance in cancer. Staphylococcal enterotoxin B (SEB) is a superantigen (SAg) and a promising compound which has lethal effects on malignant cells. In this unprecedented study, SEB was used against U937 cells in a co-culture system in the presence of human bone marrow-mesenchymal stem cells (hBM-MSCs). The effects of hBM-MSCs on the proliferation and survival of U937 cell line with SEB was assessed using MTT assay and AnnexinV/PI flowcytometry, respectively. Moreover, the expression of IL-6, IL-10, TGF-β, and inhibitor of nuclear factor kappa-B kinase (IKKb) was evaluated by real-time PCR technique. The same experiments were also carried out using hBM-MSCs-conditioned medium (hBM-MSCs-CM). The results showed that SEB reduced the proliferation and survival of U937 cell line, but hBM-MSCs or hBM-MSCs-CM suppressed the effects of SEB. Furthermore, real-timePCR demonstrated that SEB could decrease the expression of IL-6, IL-10, and TGF-β in hBM-MSCs (P < .05), while the production of IKKb was increased in comparison with the control group. These findings help us to have a broader understanding ofthe usage of SEB in the treatment of haematological malignancies, especially if it is targeted against hBM-MSCs to disrupt their supportive effects on malignant cells. © 2018 John Wiley & Sons Australia, Ltd.

Investigation of a direct effect of nanosecond pulse electric fields on mitochondria

NASA Astrophysics Data System (ADS)

Estlack, Larry E.; Roth, Caleb C.; Cerna, Cesario Z.; Wilmink, Gerald J.; Ibey, Bennett L.

2014-03-01

The unique cellular response to nanosecond pulsed electric field (nsPEF) exposure, as compared to longer pulse exposure, has been theorized to be due to permeabilization of intracellular organelles including the mitochondria. In this investigation, we utilized a high-throughput oxygen and pH sensing system (Seahorse® XF24 extracellular flux analyzer) to assess the mitochondrial activity of Jurkat and U937 cells after nsPEF. The XF Analyzer uses a transient micro-chamber of only a few μL in specialized cell culture micro-plates to enable oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) to be monitored in real-time. We found that for nsPEF exposures of 10 pulses at 10-ns pulse width and at 50 kV/cm e-field, we were able to cause an increase in OCR in both U937 and Jurkat cells. We also found that high pulse numbers (>100) caused a significant decrease in OCR. Higher amplitude 150 kV/cm exposures had no effect on U937 cells and yet they had a deleterious effect on Jurkat cells, matching previously published 24 hour survival data. These results suggest that the exposures were modulating metabolic activity in cells possibly due to direct effects on the mitochondria themselves. To validate this hypothesis, we isolated mitochondria from U937 cells and exposed them similarly and found no significant change in metabolic activity for any pulse number. In a final experiment, we removed calcium from the buffer solution that the cells were exposed in and found that no significant enhancement in metabolic activity was observed. These results suggest that direct permeabilization of the mitochondria is unlikely a primary effect of nsPEF exposure and calcium-mediated intracellular pathway activation is likely responsible for observed pulse-induced mitochondrial effects.

Antioxidant activity, anti-proliferative activity, and amino acid profiles of ethanolic extracts of edible mushrooms.

PubMed

Panthong, S; Boonsathorn, N; Chuchawankul, S

2016-10-17

Biological activities of various mushrooms have recently been discovered, particularly, immunomodulatory and antitumor activities. Herein, three edible mushrooms, Auricularia auricula-judae (AA), Pleurotus abalonus (PA) and Pleurotus sajor-caju (PS) extracted using Soxhlet ethanol extraction were evaluated for their antioxidative, anti-proliferative effects on leukemia cells. Using the Folin-Ciocalteau method and Trolox equivalent antioxidant capacity assay, phenolics and antioxidant activity were found in all sample mushrooms. Additionally, anti-proliferative activity of mushroom extracts against U937 leukemia cells was determined using a viability assay based on mitochondrial activity. PA (0.5 mg/mL) and AA (0.25-0.5 mg/mL) significantly reduced cell viability. Interestingly, PS caused a hormetic-like biphasic dose-response. Low doses (0-0.25 mg/L) of PS promoted cell proliferation up to 140% relative to control, whereas higher doses (0.50 mg/mL) inhibited cell proliferation. Against U937 cells, AA IC 50 was 0.28 ± 0.04 mg/mL, which was lower than PS or PA IC 50 (0.45 ± 0.01 and 0.49 ± 0.001 mg/mL, respectively). Furthermore, lactate dehydrogenase (LDH) leakage conferred cytotoxicity. PS and PA were not toxic to U937 cells at any tested concentration; AA (0.50 mg/mL) showed high LDH levels and caused 50% cytotoxicity. Additionally, UPLC-HRMS data indicated several phytochemicals known to support functional activities as either antioxidant or anti-proliferative. Glutamic acid was uniquely found in ethanolic extracts of AA, and was considered an anti-cancer amino acid with potent anti-proliferative effects on U937 cells. Collectively, all mushroom extracts exhibited antioxidant effects, but their anti-proliferative effects were dose-dependent. Nevertheless, the AA extract, with highest potency, is a promising candidate for future applications.

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

PubMed

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

2015-05-01

Roughly 80% of patients with acute myeloid leukaemia have high activity of Bruton's tyrosine-kinase (BTK) in their blast cells compared with normal haemopoietic cells, rendering the cells sensitive to the oral BTK inhibitor ibrutinib in vitro. We aimed to develop the biological understanding of the BTK pathway in acute myeloid leukaemia to identify clinically relevant diagnostic information that might define a subset of patients that should respond to ibrutinib treatment. We obtained acute myeloid leukaemia blast cells from unselected patients attending our UK hospital between Feb 19, 2010, and Jan 20, 2014. We isolated primary acute myeloid leukaemia blast cells from heparinised blood and human peripheral blood mononuclear cells to establish the activity of BTK in response to CD117 activation. Furthermore, we investigated the effects of ibrutinib on CD117-induced BTK activation, downstream signalling, adhesion to primary bone-marrow mesenchymal stromal cells, and proliferation of primary acute myeloid leukaemia blast cells. We used the Mann-Whitney U test to compare results between groups. We obtained acute myeloid leukaemia blast cells from 29 patients. Ibrutinib significantly inhibited CD117-mediated proliferation of primary acute myeloid leukaemia blast cells (p=0·028). CD117 activation increased BTK activity by inducing phosphorylated BTK in patients with CD117-positive acute myeloid leukaemia. Furthermore, ibrutinib inhibited CD117-induced activity of BTK and downstream kinases at a concentration of 100 nM or more. CD117-mediated adhesion of CD117-expressing blast cells to bone-marrow stromal cells was significantly inhibited by Ibrutinib at 500 nM (p=0·028) INTERPRETATION: As first-in-man clinical trials of ibrutinib in patients with acute myeloid leukaemia commence, the data suggest not all patients will respond. Our findings show that BTK has specific pro-tumoural biological actions downstream of surface CD117 activation, which are inhibited by ibrutinib. Accordingly, we propose that patients with acute myeloid leukaemia whose blast cells express CD117 should be considered for forthcoming clinical trials of ibrutinib. Worldwide Cancer Research, The Big C, UK National Institutes for Health Research, the Humane Research Trust, the Department of Higher Education and Research of the Libyan Government, and Norwich Research Park. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sensitization of U937 leukemia cells to doxorubicin by the MG132 proteasome inhibitor induces an increase in apoptosis by suppressing NF-kappa B and mitochondrial membrane potential loss

PubMed Central

2014-01-01

Background The resistance of cancerous cells to chemotherapy remains the main limitation for cancer treatment at present. Doxorubicin (DOX) is a potent antitumor drug that activates the ubiquitin-proteasome system, but unfortunately it also activates the Nuclear factor kappa B (NF-кB) pathway leading to the promotion of tumor cell survival. MG132 is a drug that inhibits I kappa B degradation by the proteasome-avoiding activation of NF-кB. In this work, we studied the sensitizing effect of the MG132 proteasome inhibitor on the antitumor activity of DOX. Methods U937 human leukemia cells were treated with MG132, DOX, or both drugs. We evaluated proliferation, viability, apoptosis, caspase-3, -8, and −9 activity and cleavage, cytochrome c release, mitochondrial membrane potential, the Bcl-2 and Bcl-XL antiapoptotic proteins, senescence, p65 phosphorylation, and pro- and antiapoptotic genes. Results The greatest apoptosis percentage in U937 cells was obtained with a combination of MG132 + DOX. Likewise, employing both drugs, we observed a decrease in tumor cell proliferation and important caspase-3 activation, as well as mitochondrial membrane potential loss. Therefore, MG132 decreases senescence, p65 phosphorylation, and the DOX-induced Bcl-2 antiapoptotic protein. The MG132 + DOX treatment induced upregulation of proapoptotic genes BAX, DIABLO, NOXA, DR4, and FAS. It also induced downregulation of the antiapoptotic genes BCL-XL and SURVIVIN. Conclusion MG132 sensitizes U937 leukemia cells to DOX-induced apoptosis, increasing its anti-leukemic effectiveness. PMID:24495648

Synthesis of a Novel Series of 2-Methylsulfanyl Fatty Acids and their Toxicity on the Human K-562 and U-937 Leukemia Cell Lines

PubMed Central

Carballeira, Néstor M.; Miranda, Carlos; Orellano, Elsie A.; González, Fernando A.

2006-01-01

The hitherto unknown 2-methylsulfanyldecanoic acid and 2-methylsulfanyldodecanoic acid were synthesized from methyl decanoate and methyl dodecanoate, respectively, through the reaction of lithium diisopropylamide and dimethyldisulfide in THF followed by saponification with potassium hydroxide in ethanol. Both α-methylsulfanylated FA were cytotoxic to the human chronic myelogenous leukemia K-562 and the human histiocytic lymphoma U-937 cell lines with EC50 values in the 200-300 μM range, which makes them more cytotoxic to these cell lines than either decanoic acid or dodecanoic acid. The cytotoxicity of the studied FA towards K-562 followed the order: 2-SCH3-12:0 > 2-SCH3-10:0 > 10:0 > 12:0 > 2-OCH3-12:0, while towards U-937 the cytotoxicity was found to be: 2-SCH3-10:0 > 2-SCH3-12:0 > 12:0 > 10:0 > 2-OCH3-12:0. These results indicate that the α-methylsulfanyl substitution increases the cytotoxicity of the C10 and C12 fatty acids towards the studied leukemia cell lines. PMID:16382579

Apigenin induces apoptosis in human leukemia cells and exhibits anti-leukemic activity in vivo via inactivation of Akt and activation of JNK

PubMed Central

Budhraja, Amit; Gao, Ning; Zhang, Zhuo; Son, Young-Ok; Cheng, Senping; Wang, Xin; Ding, Songze; Hitron, Andrew; Chen, Gang; Luo, Jia; Shi, Xianglin

2015-01-01

In this study, we investigated the functional role of Akt and JNK signaling cascades in apigenin-induced apoptosis in U937 human leukemia cells and anti-leukemic activity of apigenin in vivo. Apigenin-induced apoptosis by inactivation of Akt with a concomitant activation of JNK, Mcl-1 and Bcl-2 down-regulation, cytochrome c release from mitochondria and activation of caspases. Constitutively active myristolated Akt prevented apigenin-induced JNK, caspases activation, and apoptosis. Conversely, LY294002 and a dominant negative construct of Akt potentiated apigenin-induced apoptosis in leukemia cells. Interruption of JNK pathway showed marked reduction in apigenin-induced caspases activation and apoptosis in leukemia cells. Furthermore, in vivo administration of apigenin resulted in attenuation of tumor growth in U937 xenografts accompanied inactivation of Akt and activation of JNK. Attenuation of tumor growth in U937 xenografts by apigenin raises the possibility that apigenin may have clinical implications and can be further tested for incorporating in leukemia treatment regimens. PMID:22084167

Effects of haloperidol, clozapine and olanzapine on the survival of human neuronal and immune cells in vitro.

PubMed

Heiser, Philip; Enning, Frank; Krieg, Jürgen-Christian; Vedder, Helmut

2007-11-01

Cytotoxic effects on neuronal as well as on immune cells have been reported for both typical and atypical antipsychotic drugs. We evaluated the effects of different concentrations of a typical (haloperidol) and two atypical (clozapine, olanzapine) antipsychotics on the survival of human neuronal (SH-SY5Y cells) and immune cells (U937 cells) by determining the metabolic activity after 24 h of incubation by the modified tetrazolium method. The dopaminergic neuroblastoma SH-SY5Y and the lymphoma U-937 cell line are well established models for in vitro investigations. To further elucidate possible mechanisms of action we also determined the ATP content in the cultured cells. After experimental treatment, significant effects were detected by Kruskal Wallis test for all treatment conditions. Post-hoc tests (Dunn's method) showed that haloperidol and clozapine at the two highest concentrations (25 and 50 microg/ml) caused a significant decrease of metabolic activity in both cell systems, which was also detectable after treatment with clozapine at a concentration of 12.5 microg/ml in U937 cells. In contrast, olanzapine induced a significant increase in metabolic activity of SH-SY5Y cells at all concentrations except for the concentration of 3.1 microg/ml, whereas the metabolic activity in U937 cells was increased at concentrations of 1.6 and 6.25 microg/ml. For the determination of ATP content, the LD(50) values of the metabolic activity were used, except for olanzapine for which no distinct LD(50) value was available. Significant changes were detected for all treatments and post-hoc tests revealed that haloperidol caused a significant decrease compared to the control condition in both cell systems. These findings suggest that antipsychotic substances of different classes exert differential metabolic effects in both neuronal and immune cell systems.

Cytokine profiling of docetaxel-resistant castration-resistant prostate cancer.

PubMed

Mahon, K L; Lin, H-M; Castillo, L; Lee, B Y; Lee-Ng, M; Chatfield, M D; Chiam, K; Breit, S N; Brown, D A; Molloy, M P; Marx, G M; Pavlakis, N; Boyer, M J; Stockler, M R; Daly, R J; Henshall, S M; Horvath, L G

2015-04-14

Docetaxel improves symptoms and survival in metastatic castration-resistant prostate cancer (CRPC). However, ∼50% of patients are chemoresistant. This study examined whether changes in cytokine levels predict for docetaxel resistance in vitro and in a clinical cohort. PC3 cells or their docetaxel-resistant subline (PC3Rx) were co-cultured with U937 monocytes, with and without docetaxel treatment, and cytokine levels were measured. The circulating levels of 28 cytokines were measured pre-/post cycle 1 of docetaxel from 55 men with CRPC, and compared with prostate-specific antigen (PSA) response. PC3Rx-U937 co-culture expressed more cytokines, chiefly markers of alternative macrophage differentiation, compared with PC3-U937 co-culture. Docetaxel treatment enhanced cytokine production by PC3Rx-U937 co-culture, while reducing cytokine levels in PC3-U937. In patients, changes in the levels of seven circulating cytokines (macrophage inhibitory cytokine 1 (MIC1), interleukin (IL)-1ra, IL-1β, IL-4, IL-6, IL-12 and IFNγ) after cycle 1 of docetaxel were associated with progressive disease (all P<0.05). The combination of changes in MIC1, IL-4 and IL-6 most strongly predicted PSA response (P=0.002). In vitro studies suggest docetaxel resistance is mediated, at least in part, by cytokines induced by the interaction between the docetaxel-resistant tumour cells and macrophages. Early changes in circulating cytokine levels were associated with docetaxel resistance in CRPC patients. When considered together, these data suggest a significant role for the inflammatory response and macrophages in the development of docetaxel resistance in CRPC.

Role of the MAPK pathway in the observed bystander effect in lymphocytes co-cultured with macrophages irradiated with γ-rays or carbon ions.

PubMed

Dong, Chen; He, Mingyuan; Ren, Ruiping; Xie, Yuexia; Yuan, Dexiao; Dang, Bingrong; Li, Wenjian; Shao, Chunlin

2015-04-15

The radiation-induced bystander effect (RIBE) has potential implications in cancer risks from space particle radiation; however, the mechanisms underlying RIBE are unclear. The role of the MAPK pathway in the RIBEs of different linear energy transfer (LET) was investigated. Human macrophage U937 cells were irradiated with γ-rays or carbon ions and then co-cultured with nonirradiated HMy2.CIR (HMy) lymphocytes for different periods. The activation of MAPK proteins and the generation of intracellular nitric oxide (NO) and reactive oxygen species (ROS) in the irradiated U937 cells were measured. Micronuclei (MN) formation in the HMy cells was applied to evaluate the bystander damage. Some U937 cells were pretreated with different MAPK inhibitors before irradiation. Additional MN formation was induced in the HMy cells after co-culturing with irradiated U937 cells, and the yield of this bystander MN formation was dependent on the co-culture period with γ-ray irradiation but remained high after 1h of co-culture with carbon irradiation. Further investigations disclosed that the time response of the RIBEs had a relationship with LET, where ERK played a different role from JNK and p38 in regulating RIBEs by regulating the generation of the bystander signaling factors NO and ROS. The finding that the RIBE of high-LET radiation could persist for a much longer period than that of γ-rays implies that particle radiation during space flight could have a high risk of long-term harmful effects. An appropriate intervention targeting the MAPK pathway may have significant implications in reducing this risk. Copyright © 2015 Elsevier Inc. All rights reserved.

Preclinical evaluation of WYE-687, a mTOR kinase inhibitor, as a potential anti-acute myeloid leukemia agent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Feng; Wang, Lingling; Shen, Yunfeng

Mammalian target of rapamycin (mTOR) as a potential drug target for treatment of acute myeloid leukemia (AML). Here, we investigated the potential anti-leukemic activity by WYE-687, a potent mTOR kinase inhibitor. We demonstrated that WYE-687 potently inhibited survival and proliferation of established (HL-60, U937, AML-193 and THP-1 lines) and human AML progenitor cells. Yet, same WYE-687 treatment was non-cytotoxic to the primary peripheral blood mononuclear leukocytes (PBMCs) isolated from healthy donors. WYE-687 induced caspase-dependent apoptotic death in above AML cells/progenitor cells. On the other hand, the pan-caspase inhibitor (Z-VAD-FMK), the caspase-3 specific inhibitor (Z-DEVD-FMK) or the caspase-9 specific inhibitor (z-LEHD-fmk)more » attenuated WYE-687-induced cytotoxicity. At the molecular level, WYE-687 concurrently inhibited activation of mTORC1 (p70S6K1 and S6 phosphorylations) and mTORC2 (AKT Ser-473 and FoxO1/3a phosphorylations), whiling downregulating mTORC1/2-regulated genes (Bcl-xL and hypoxia-inducible factor 1/2α) in both HL-60/U937 cells and human AML progenitor cells. In vivo, oral administration of WYE-687 potently inhibited U937 leukemic xenograft tumor growth in severe combined immunodeficient (SCID) mice, without causing significant toxicities. In summary, our results demonstrate that targeting mTORC1/2 by WYE-687 leads to potent antitumor activity in preclinical models of AML. - Highlights: • WYE-687 inhibits survival and proliferation of human AML cells/progenitor cells. • WYE-687 induces apoptotic death of human AML cells/progenitor cells. • WYE-687 inhibits mTORC1/2 activation in human AML cells/progenitor cells. • WYE-687 inhibits U937 xenograft growth in SCID mice.« less

New sesquiterpene lactones from Ambrosia cumanensis Kunth.

PubMed

Jimenez-Usuga, Nora Del Socorro; Malafronte, Nicola; Cotugno, Roberta; De Leo, Marinella; Osorio, Edison; De Tommasi, Nunziatina

2016-09-01

Eleven sesquiterpene lactones, including three new natural products (1-3), were isolated from the n-butanolic extract of Ambrosia cumanensis Kunth. aerial parts. The structure of all isolated compounds was elucidated by 1D- and 2D-NMR, and MS analyses. All compounds were tested for their antiproliferative activity on HeLa, Jurkat, and U937 cell lines. Compound 3, 2,3-dehydropsilostachyn C, showed cytotoxic activity with different potency in all cell lines. By means of flow cytometric studies, compound 3 was demonstrated to induce in Jurkat cells a G2/M cell cycle block, while in U937 elicited both cytostatic and cytotoxic responses. Copyright © 2016 Elsevier B.V. All rights reserved.

Altered regulation of ELAVL1/HuR in HLA-B27-expressing U937 monocytic cells.

PubMed

Sahlberg, Anna S; Ruuska, Marja; Granfors, Kaisa; Penttinen, Markus A

2013-01-01

To investigate the role of HLA-B27 expression in the regulation of RNA binding protein (RBP) Embryonic Lethal Abnormal Vision (ELAV) L1/Human antigen R (HuR) expression in Salmonella-infected or LPS-stimulated human monocytic cells, since HuR is a critical regulator of the post-transcriptional fate of many genes (e.g. TNFα) important in inflammatory response. U937 monocytic cells were stably transfected with pSV2neo resistant vector (mock), wild type HLA-B27, or mutated HLA-B27 with amino acid substitutions in the B pocket. Cells were differentiated, infected with Salmonella enteritidis or stimulated with lipopolysaccharide. The expression levels of HuR protein and cleavage products (CP1 and CP2) were detected by Western blotting and flow cytometry. Specific inhibitors were used to study the role of PKR and p38 in HuR expression and generation of CPs. TNFα and IL-10 secretion after p38 and PKR inhibition were measured by ELISA. Full length HuR is overexpressed and HuR cleavage is disturbed in U937 monocytic cells expressing HLA-B27 heavy chains (HC). Increased full length HuR expression, disturbed cleavage and reduced dependence on PKR after infection correlate with the expression of glutamic acid 45 in the B pocket that is linked to the misfolding of HLA-B27. Results show that the expression of HLA-B27 HCs modulates the intracellular environment of U937 monocyte/macrophages by altering HuR regulation. This phenomenon is at least partly dependent on the misfolding feature of the B27 molecule. Since HuR is an important regulator of multiple genes involved in inflammatory response observations offer an explanation how HLA-B27 may modulate inflammatory response.

Calcium and the heat-shock response in the human monocytic line U-937.

PubMed

Kantengwa, S; Capponi, A M; Bonventre, J V; Polla, B S

1990-07-01

In the human monocytic line U-937, 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] increases cytosolic free calcium concentration ([Ca2+]i). 1,25-(OH)2D3 also enhances the synthesis of heat-shock proteins (HSPs) when U-937 cells are exposed to elevated temperatures. To establish whether these two effects of 1,25-(OH)2D3 are related, we examined the effects of calcium on the heat-shock (HS) response, as well as the influence of 1,25-(OH)2D3 on this system. The equilibrium dissociation constant (Kd) of the fluorescent probe used to measure [Ca2+]i, fura-2, at 37 and 45 degrees C was found to be 191 and 234 nM, respectively. Exposure of U-937 cells to 45 degrees C did not increase [Ca2+]i under conditions in which active efflux of the dye was prevented by the organic anion transport inhibitor probenecid (1 mM). In cells preincubated in calcium-free medium, with subsequent addition of 4 mM EGTA before HS, or exposed to the calmodulin antagonist N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide (W-7), the increase in HSPs synthesis was not affected. Cell viability, assessed by [3H]thymidine uptake, was not different between cells exposed to HS in calcium-containing or calcium-free media. Moreover, the effects of 1,25-(OH)2D3 on the HS response were also observed in a calcium-depleted medium, indicating that the effects of 1,25-(OH)2D3 on HSP synthesis were not mediated by [Ca2+]i.

Resveratrol strongly enhances the retinoic acid-induced superoxide generating activity via up-regulation of gp91-phox gene expression in U937 cells.

PubMed

Kikuchi, Hidehiko; Mimuro, Hitomi; Kuribayashi, Futoshi

2018-01-01

The membrane bound cytochrome b 558 composed of gp91-phox and p22-phox proteins, and cytosolic proteins p40-, p47-and p67-phox are important components of superoxide (O 2 - )-generating system in phagocytes. Here, we describe that resveratrol, a pleiotropic phytochemical belonging to the stilbenoids, dramatically activates the O 2 - -generating system during retinoic acid (RA)-induced differentiation of human monoblastic leukemia U937 cells to macrophage-like cells. When U937 cells were cultured in the presence of RA and resveratrol, the O 2 - -generating activity increased more than 5-fold compared with that in the absence of the latter. Semiquantitative RT-PCR showed that co-treatment with RA and resveratrol strongly enhanced transcription of the gp91-phox compared with those of the RA-treatment only. On the other hand, immunoblot analysis revealed that co-treatment with RA and resveratrol caused remarkable accumulation of protein levels of gp91-phox (to 4-fold), p22-phox (to 5-fold) and p47-phox (to 4-fold) compared with those of the RA-treatment alone. In addition, ChIP assay suggested that resveratrol participates in enhancing the gene expression of gp91-phox via promoting acetylation of Lys-9 residues and Lys-14 residues of histone H3 within chromatin around the promoter regions of the gene. These results suggested that resveratrol strongly enhances the RA-induced O 2 - -generating activity via up-regulation of gp91-phox gene expression in U937 cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Microgravity modifies protein kinase C isoform translocation in the human monocytic cell line U937 and human peripheral blood T-cells

NASA Technical Reports Server (NTRS)

Hatton, Jason P.; Gaubert, Francois; Cazenave, Jean-Pierre; Schmitt, Didier; Hashemi, B. B. (Principal Investigator); Hughes-Fulford, M. (Principal Investigator)

2002-01-01

Individual protein kinase C (PKC) isoforms fulfill distinct roles in the regulation of the commitment to differentiation, cell cycle arrest, and apoptosis in both monocytes and T-cells. The human monocyte like cell line U937 and T-cells were exposed to microgravity, during spaceflight and the translocation (a critical step in PKC signaling) of individual isoforms to cell particulate fraction examined. PKC activating phorbol esters induced a rapid translocation of several PKC isoforms to the particulate fraction of U937 monocytes under terrestrial gravity (1 g) conditions in the laboratory. In microgravity, the translocation of PKC beta II, delta, and epsilon in response to phorbol esters was reduced in microgravity compared to 1 g, but was enhanced in weak hypergravity (1.4 g). All isoforms showed a net increase in particulate PKC following phorbol ester stimulation, except PKC delta which showed a net decrease in microgravity. In T-cells, phorbol ester induced translocation of PKC delta was reduced in microgravity, compared to 1 g, while PKC beta II translocation was not significantly different at the two g-levels. These data show that microgravity differentially alters the translocation of individual PKC isoforms in monocytes and T-cells, thus providing a partial explanation for the modifications previously observed in the activation of these cell types under microgravity.

Annexin A2-S100A10 heterotetramer is upregulated by PML/RARα fusion protein and promotes plasminogen-dependent fibrinolysis and matrix invasion in acute promyelocytic leukemia.

PubMed

Huang, Dan; Yang, Yan; Sun, Jian; Dong, Xiaorong; Wang, Jiao; Liu, Hongchen; Lu, Chengquan; Chen, Xueyu; Shao, Jing; Yan, Jinsong

2017-09-01

Aberrant expression of annexin A2-S100A10 heterotetramer (AIIt) associated with PML/RARα fusion protein causes lethal hyperfibrinolysis in acute promyelocytic leukemia (APL), but the mechanism is unclear. To facilitate the investigation of regulatory association between ANXA2 and promyelocytic leukemia/retinoic acid receptor a (PML/RARα) fusion protein, this work was performed to determine the transcription start site of ANXA2 promoter with rapid amplification of 5'-cDNA ends analysis. Zinc-induced U937/PR9 cells expressed PML/RARα fusion protein, and resultant increases in ANXA2 transcripts and translational expressions of both ANXA2 and S100A10, while S100A10 transcripts remained constitutive. The transactivation of ANXA2 promoter by PML/RARα fusion protein was 3.29 ± 0.13 fold higher than that by control pSG5 vector or wild-type RARα. The overexpression of ANXA2 in U937 transfected with full-length ANXA2 cDNA was associated with increased S100A10 subunit, although S100A10 transcripts remained constitutive. The tPA-dependent initial rate of plasmin generation (IRPG) in zinc-treated U937/PR9 increased by 2.13-fold, and cell invasiveness increased by 27.6%. Antibodies against ANXA2, S100A10, or combination of both all remarkably inhibited the IRPG and invasiveness in U937/PR9 and NB4. Treatment of zinc-induced U937/PR9 or circulating APL blasts with all-trans retinoic acid (ATRA) significantly reduced cell surface ANXA2 and S100A10 and associated reductions in IRPG and invasiveness. Thus, PML/RARα fusion protein transactivated the ANXA2 promoter to upregulate ANXA2 and accumulate S100A10. Increased AIIt promoted IRPG and invasiveness, both of which were partly abolished by antibodies against ANXA2 and S100A10 or by ATRA.

Synthesis, structural characterization, and pro-apoptotic activity of 1-indanone thiosemicarbazone platinum(II) and palladium(II) complexes: potential as antileukemic agents.

PubMed

Gómez, Natalia; Santos, Diego; Vázquez, Ramiro; Suescun, Leopoldo; Mombrú, Alvaro; Vermeulen, Monica; Finkielsztein, Liliana; Shayo, Carina; Moglioni, Albertina; Gambino, Dinorah; Davio, Carlos

2011-08-01

In the search for alternative chemotherapeutic strategies against leukemia, various 1-indanone thiosemicarbazones, as well as eight novel platinum(II) and palladium(II) complexes, with the formula [MCl₂(HL)] and [M(HL)(L)]Cl, derived from two 1-indanone thiosemicarbazones were synthesized and tested for antiproliferative activity against the human leukemia U937 cell line. The crystal structure of [Pt(HL1)(L1)]Cl·2MeOH, where L1=1-indanone thiosemicarbazone, was solved by X-ray diffraction. Free thiosemicarbazone ligands showed no antiproliferative effect, but the corresponding platinum(II) and palladium(II) complexes inhibited cell proliferation and induced apoptosis. Platinum(II) complexes also displayed selective apoptotic activity in U937 cells but not in peripheral blood monocytes or the human hepatocellular carcinoma HepG2 cell line used to screen for potential hepatotoxicity. Present findings show that, in U937 cells, 1-indanone thiosemicarbazones coordinated to palladium(II) were more cytotoxic than those complexed with platinum(II), although the latter were found to be more selective for leukemic cells suggesting that they are promising compounds with potential therapeutic application against hematological malignancies. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Toxicity of silver nanoparticles towards tumoral human cell lines U-937 and HL-60.

PubMed

Barbasz, Anna; Oćwieja, Magdalena; Roman, Maciej

2017-08-01

The toxicity of three types of silver nanoparticles towards histiocytic lymphoma (U-937) and human promyelocytic cells (HL-60) was studied. The nanoparticles were synthesized in a chemical reduction method using sodium borohydride. Trisodium citrate and cysteamine hydrochloride were used to generate a negative and positive nanoparticle surface charge. The evaluation of cell viability, membrane integrity, antioxidant activity and the induction of inflammation were used to evaluate the difference in cellular response to the nanoparticle treatment. The results revealed that the cysteamine-stabilized (positively charged) nanoparticles (SBATE) were the least toxic although they exhibited a similar ion release profile as the unmodified (negatively charged) nanoparticles obtained using sodium borohydride (SBNM). Citrate-stabilized nanoparticles (SBTC) induced superoxide dismutase (SOD) activity in the HL-60 cells and total antioxidant activity in the U-937 cells despite their resistance to oxidative dissolution. The toxicity of SBNM nanoparticles was manifested in the disruption of membrane integrity, decrease in the mitochondrial functions of cells and the induction of inflammation. These findings allowed to conclude that mechanism of silver nanoparticle cytotoxicity is the combination of effects coming from the surface charge of nanoparticles, released silver ions and biological activity of stabilizing agent molecules. Copyright © 2017 Elsevier B.V. All rights reserved.

Synergistic effect of muramyldipeptide with lipopolysaccharide or lipoteichoic acid to induce inflammatory cytokines in human monocytic cells in culture.

PubMed

Yang, S; Tamai, R; Akashi, S; Takeuchi, O; Akira, S; Sugawara, S; Takada, H

2001-04-01

An analog of 1alpha,25-dihydroxyvitamin D3, 22-oxyacalcitriol (OCT), differentiated human monocytic THP-1 and U937 cells to express membrane CD14 and rendered the cells responsive to bacterial cell surface components. Both THP-1 and U937 cells expressed Toll-like receptor 4 (TLR4) on the cell surface and TLR4 mRNA in the cells, irrespective of OCT treatment. In contrast, OCT-treated U937 cells scarcely expressed TLR2 mRNA, while OCT-treated THP-1 cells expressed this transcript. Muramyldipeptide (MDP) by itself exhibited only a weak ability to induce secretion of inflammatory cytokines such as interleukin-8 (IL-8) in the OCT-differentiated THP-1 cells but showed marked synergistic effects with Salmonella lipopolysaccharide (LPS) or lipoteichoic acid (LTA) from Staphylococcus aureus, both of which exhibited strong activities. Combinatory stimulation with LPS plus LTA did not show a synergistic effect on OCT-differentiated THP-1 cells. Similar results were observed in OCT-differentiated U937 cells, although combination experiments were carried out only with MDP plus LPS. Anti-CD14 monoclonal antibody (MAb) MY4, anti-TLR4 MAb HTA125, and the synthetic lipid A precursor LA-14-PP almost completely inhibited the IL-8-inducing activities of LTA as well as LPS on OCT-treated THP-1 cells, but these treatments increased MDP activity. OCT-treated THP-1 cells primed with MDP exhibited enhanced production of IL-8 upon stimulation with LPS, while the cells primed with LPS showed no change in production upon stimulation with MDP. MDP up-regulated mRNA expression of an adapter molecule to TLRs, MyD88, to an extent similar to that for LPS in OCT-treated THP-1 cells. These findings suggested that LTA as well as LPS activated human monocytic cells in a CD14- and TLR4-dependent manner, whereas MDP exhibited activity in a CD14-, TLR4-, and probably TLR2-independent manner and exhibited synergistic and priming effects on the cells for cytokine production in response to various bacterial components.

Cloning of a long HIV-1 readthrough transcript and detection of an increased level of early growth response protein-1 (Egr-1) mRNA in chronically infected U937 cells.

PubMed

Dron, M; Hameau, L; Benboudjema, L; Guymarho, J; Cajean-Feroldi, C; Rizza, P; Godard, C; Jasmin, C; Tovey, M G; Lang, M C

1999-01-01

To identify the pathways involved in HIV-1 modification of cellular gene expression, chronically infected U937 cells were screened by mRNA differential display. A chimeric transcript consisting of the 3' end of the LTR of a HIV-1 provirus, followed by 3.7 kb of cellular RNA was identified suggesting that long readthrough transcription might be one of the mechanisms by which gene expression could be modified in individual infected cells. Such a phenomenon may also be the first step towards the potential transduction of cellular sequences. Furthermore, the mRNA encoding for the transcription factor Egr-1 was detected as an over-represented transcript in infected cells. Northern blot analysis confirmed the increase of Egr-1 mRNA content in both HIV-1 infected promonocytic U937 cells and T cell lines such as Jurkat and CEM. Interestingly a similar increase of Egr-1 mRNA has previously been reported to occur in HTLV-1 and HTLV-2 infected T cell lines. Despite the consistent increase in the level of Egr-1 mRNA, the amount of the encoded protein did not appear to be modified in HIV-1 infected cells, suggesting an increased turn over of the protein in chronically infected cells.

Cervical cancer cell supernatants induce a phenotypic switch from U937-derived macrophage-activated M1 state into M2-like suppressor phenotype with change in Toll-like receptor profile.

PubMed

Sánchez-Reyes, Karina; Bravo-Cuellar, Alejandro; Hernández-Flores, Georgina; Lerma-Díaz, José Manuel; Jave-Suárez, Luis Felipe; Gómez-Lomelí, Paulina; de Celis, Ruth; Aguilar-Lemarroy, Adriana; Domínguez-Rodríguez, Jorge Ramiro; Ortiz-Lazareno, Pablo Cesar

2014-01-01

Cervical cancer (CC) is the second most common cancer among women worldwide. Infection with human papillomavirus (HPV) is the main risk factor for developing CC. Macrophages are important immune effector cells; they can be differentiated into two phenotypes, identified as M1 (classically activated) and M2 (alternatively activated). Macrophage polarization exerts profound effects on the Toll-like receptor (TLR) profile. In this study, we evaluated whether the supernatant of human CC cells HeLa, SiHa, and C-33A induces a shift of M1 macrophage toward M2 macrophage in U937-derived macrophages. The results showed that soluble factors secreted by CC cells induce a change in the immunophenotype of macrophages from macrophage M1 into macrophage M2. U937-derived macrophages M1 released proinflammatory cytokines and nitric oxide; however, when these cells were treated with the supernatant of CC cell lines, we observed a turnover of M1 toward M2. These cells increased CD163 and IL-10 expression. The expression of TLR-3, -7, and -9 is increased when the macrophages were treated with the supernatant of CC cells. Our result strongly suggests that CC cells may, through the secretion of soluble factors, induce a change of immunophenotype M1 into M2 macrophages.

Leukaemic infiltration and cytomegalovirus retinitis in a patient with acute T-cell lymphoblastic leukaemia in complete remission.

PubMed

Saldaña Garrido, J D; Martínez Rubio, M; Carrión Campo, R; Moya Moya, M A; Rico Sergado, L

2017-03-01

A 43-year-old woman in remission from T- cell acute lymphoblastic leukaemia was referred to our hospital with suspected leukaemic retinitis. The funduscopic examination of her left eye revealed multifocal yellow-white peripheral retinitis and retinal haemorrhage. The patient was treated for cytomegalovirus retinitis after an extended haematological investigation showed no abnormalities. Initial improvement was followed by papillitis in the left eye and motility restriction in the right eye. Magnetic resonance and lumbar puncture confirmed leukaemia relapse. Specific treatment was initiated with complete resolution. Ocular involvement may precede haematological leukaemia relapse. Physicians should be alerted when ocular symptoms appear in these cases. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

The differential role of human macrophage in triggering secondary bystander effects after either gamma-ray or carbon beam irradiation

PubMed Central

Dong, Chen; He, Mingyuan; Tu, Wenzhi; Konishi, Teruaki; Liu, Weili; Xie, Yuexia; Dang, Bingrong; Li, Wenjian; Uchihori, Yukio; Hei, Tom K.; Shao, Chunlin

2015-01-01

The abscopal effect could be an underlying factor in evaluating prognosis of radiotherapy. This study established an in vitro system to examine whether tumor-generated bystander signals could be transmitted by macrophages to further trigger secondary cellular responses after different irradiations, where human lung cancer NCI-H446 cells were irradiated with either γ-rays or carbon ions and co-cultured with human macrophage U937 cells, then these U937 cells were used as a bystander signal transmitter and co-cultured with human bronchial epithelial cells BEAS-2B. Results showed that U937 cells were only activated by γ-irradiated NCI-H446 cells so that the secondary injuries in BEAS-2B cells under carbon ion irradiation were weaker than γ-rays. Both TNF-α and IL-1α were involved in γ-irradiation induced secondary bystander effect but only TNF-α contributed to the carbon ion induced response. Further assay disclosed that IL-1α but not TNF-α was largely responsible for the activation of macrophages and the formation of micronucleus in BEAS-2B cells. These data suggest that macrophages could transfer secondary bystander signals and play a key role in the secondary bystander effect of photon irradiation while carbon ion irradiation has conspicuous advantage due to its reduced secondary injury. PMID:25896631

The differential role of human macrophage in triggering secondary bystander effects after either gamma-ray or carbon beam irradiation.

PubMed

Dong, Chen; He, Mingyuan; Tu, Wenzhi; Konishi, Teruaki; Liu, Weili; Xie, Yuexia; Dang, Bingrong; Li, Wenjian; Uchihori, Yukio; Hei, Tom K; Shao, Chunlin

2015-07-10

The abscopal effect could be an underlying factor in evaluating prognosis of radiotherapy. This study established an in vitro system to examine whether tumor-generated bystander signals could be transmitted by macrophages to further trigger secondary cellular responses after different irradiations, where human lung cancer NCI-H446 cells were irradiated with either γ-rays or carbon ions and co-cultured with human macrophage U937 cells, then these U937 cells were used as a bystander signal transmitter and co-cultured with human bronchial epithelial cells BEAS-2B. Results showed that U937 cells were only activated by γ-irradiated NCI-H446 cells so that the secondary injuries in BEAS-2B cells under carbon ion irradiation were weaker than γ-rays. Both TNF-α and IL-1α were involved in the γ-irradiation induced secondary bystander effect but only TNF-α contributed to the carbon ion induced response. Further assay disclosed that IL-1α but not TNF-α was largely responsible for the activation of macrophages and the formation of micronucleus in BEAS-2B cells. These data suggest that macrophages could transfer secondary bystander signals and play a key role in the secondary bystander effect of photon irradiation, while carbon ion irradiation has conspicuous advantage due to its reduced secondary injury. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

NF-kB activity-dependent P-selectin involved in ox-LDL-induced foam cell formation in U937 cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yi, E-mail: wangyi2004a@126.com; Wang, Xiang; Sun, Minghui

Highlights: {yields} Ox-LDL induced foam cell formation in the human U937 promonocytic cell line in a dose- and time-dependent manner. {yields} Ox-LDL induced expression of P-selectin through degradation of IkBa and augment of NF-kB activity and protein level during macrophage-derived foam cell formation. {yields} P-selectin and NF-kB may be identified as pivotal regulators of ox-LDL-induced foam cell formation. {yields} Therapy based on the inhibition of P-selectin and NF-kB may complement conventional treatments to prevent atherosclerosis. -- Abstract: Oxidized low-density lipoprotein (ox-LDL) plays a critical role in regulation of atherosclerosis. However, little is known about the role of Nuclear factor kBmore » (NF-kB) activity-dependent P-selectin in ox-LDL-induced foam cell formation during atherosclerosis. In this study, we first investigated ox-LDL induced foam cell formation in the human U937 promonocytic cell line in a dose- and time-dependent manner. Treatment of U937 cells with ox-LDL increased lipid accumulation as well as intracellular cholesterol content. Next, a comparative analysis of gene expression profiling using cDNA microarray and Real-time-PCR indicated that ox-LDL exposure induced, in three treated groups, an extremely marked increase in the mRNA level of P-selectin. Protein levels of P-selectin and its upstream regulators IkBa and NF-kB showed that NF-kB pathway is involved in the ox-LDL-induced foam cell formation. Finally, overexpression of NF-kB significantly accelerated, whereas, inhibition of NF-kB with siRNA remarkably attenuated ox-LDL-induced macrophage-derived foam cell formation. It was concluded that the activity of NF-kB is augmented during macrophage-derived foam cell formation. Activation of NF-kB increased, whereas, inhibition of NF-kB decreased ox-LDL-induced P-selectin expression and lipid accumulation in macrophages, suggesting ox-LDL induced expression of P-selectin through degradation of IkBa and activation of NF-kB in the regulation of foam cell formation.« less

Infectivity of five different types of macrophages by Leishmania infantum.

PubMed

Maia, C; Rolão, N; Nunes, M; Gonçalves, L; Campino, L

2007-08-01

Leishmania are intracellular parasites that multiply as the amastigote form in the macrophages of their vertebrate hosts. Since vaccines against leishmaniases are still under development, the control of these diseases relies on prompt diagnosis and chemotherapy in infected humans as well as in dogs, which are the main reservoir of Leishmania infantum, in Mediterranean countries. To establish the macrophage type to be used as an in vitro model for antileishmanial chemotherapeutic studies, we analysed the susceptibility of human peripheral blood derived macrophages, macrophages derived from mouse bone marrow, mouse peritoneal macrophages and macrophages differentiated from cell lines U-937 and DH82 to infection by two L. infantum strains, one obtained from a human leishmanial infection and other from a canine infection. Both strains displayed comparable behaviour in their capacity of infecting the different macrophage types. Human peripheral blood macrophages and DH82 cells were less infectable by both strains. U-937, mouse peritoneal macrophages and mouse bone marrow derived macrophages are the most active cells to phagocytose the parasites. However, U-937 cell line appears to be the most useful as Leishmania infection model providing an unlimited source of homogeneous host cells with reproducibility of the results, is less time consuming, less expensive and tolerate high doses of first line drugs for human and canine visceral leishmaniasis treatment.

Symptoms of adult chronic and acute leukaemia before diagnosis: large primary care case-control studies using electronic records.

PubMed

Shephard, Elizabeth A; Neal, Richard D; Rose, Peter W; Walter, Fiona M; Hamilton, Willie

2016-03-01

Leukaemia is the eleventh commonest UK cancer. The four main subtypes have different clinical profiles, particularly between chronic and acute types. To identify the symptom profiles of chronic and acute leukaemia in adults in primary care. Matched case-control studies using Clinical Practice Research Datalink records. Putative symptoms of leukaemia were identified in the year before diagnosis. Conditional logistic regression was used for analysis, and positive predictive values (PPVs) were calculated to estimate risk. Of cases diagnosed between 2000 and 2009, 4655 were aged ≥40 years (2877 chronic leukaemia (CL), 937 acute leukaemia (AL), 841 unreported subtype). Ten symptoms were independently associated with CL, the three strongest being: lymphadenopathy (odds ratio [OR] 22, 95% confidence interval [CI] = 13 to 36), weight loss (OR 3.0, 95% CI = 2.1 to 4.2), and bruising (OR 2.3, 95% CI = 1.6 to 3.2). Thirteen symptoms were independently associated with AL, the three strongest being: nosebleeds and/or bleeding gums (OR 5.7, 95% CI = 3.1 to 10), fever (OR 5.3, 95% CI = 2.7 to 10), and fatigue (OR 4.4, 95% CI = 3.3 to 6.0). No individual symptom or combination of symptoms had a PPV >1%. The symptom profiles of CL and AL have both overlapping and distinct features. This presents a dichotomy for GPs: diagnosis, by performing a full blood count, is easy; however, the symptoms of leukaemia are non-specific and of relatively low risk. This explains why many leukaemia diagnoses are unexpected findings. © British Journal of General Practice 2016.

Tryptophol induces death receptor (DR) 5-mediated apoptosis in U937 cells.

PubMed

Inagaki, Shyuichiro; Morimura, Shigeru; Tang, Yueqin; Akutagawa, Hiroshi; Kida, Kenji

2007-08-01

Tryptophol is a natural component isolated from vinegar produced from the boiled extract of black soybean. We have reported that tryptophol induces apoptosis in U937 cells via activation of caspase-8 followed by caspase-3. Tryptophol, however, did not affect human peripheral blood lymphocytes (PBL). In this study, we found that tryptophol enhances formation of a death-inducing signaling complex including death receptor (DR) 5. Cell viability and induction of apoptosis by tryptophol was reduced by transfection with decoy receptor (DcR) 1. These results indicate that tryptophol induces apoptosis through DR5 and that the resistance of PBL to tryptophol-induced apoptosis might be due to competition from DcR1.

Effects of Liposomal Compositions with Oxidized Dextrans on Functional Activity of U937 Macrophage-Like Cells In Vitro.

PubMed

Kozhin, P M; Chechushkov, A V; Zaitseva, N S; Lemza, A E; Men'shchikova, E B; Troitskii, A V; Shkurupy, V A

2015-11-01

We studied the effects of liposomal pharmaceutical compositions with oxidized dextrans on functional activity of U937 monocyte/macrophage-like cells. Liposomes in the emulsion contained oxidized dextran with a molecular weights of 40 kDa or 70 kDa or isonicotinic acid hydrazide (INAH) conjugated with oxidized dextran (40 kDa). Cell viability was evaluated by MTT test; mitochondrial transmembrane potential and production of superoxide anion and H2O2 were studied by fluorescent methods. The studied compositions exhibited no cytotoxic effect and even improved cell viability and mitochondrial respiration. Liposomes with oxidized 40 kDa dextran, including those with INAH-conjugated dextran, inhibited production of superoxide anion, but increased H2O2 generation.

Protein C Inhibitor (PCI) Binds to Phosphatidylserine Exposing Cells with Implications in the Phagocytosis of Apoptotic Cells and Activated Platelets

PubMed Central

Rieger, Daniela; Assinger, Alice; Einfinger, Katrin; Sokolikova, Barbora; Geiger, Margarethe

2014-01-01

Protein C Inhibitor (PCI) is a secreted serine protease inhibitor, belonging to the family of serpins. In addition to activated protein C PCI inactivates several other proteases of the coagulation and fibrinolytic systems, suggesting a regulatory role in hemostasis. Glycosaminoglycans and certain negatively charged phospholipids, like phosphatidylserine, bind to PCI and modulate its activity. Phosphatidylerine (PS) is exposed on the surface of apoptotic cells and known as a phagocytosis marker. We hypothesized that PCI might bind to PS exposed on apoptotic cells and thereby influence their removal by phagocytosis. Using Jurkat T-lymphocytes and U937 myeloid cells, we show here that PCI binds to apoptotic cells to a similar extent at the same sites as Annexin V, but in a different manner as compared to live cells (defined spots on ∼10–30% of cells). PCI dose dependently decreased phagocytosis of apoptotic Jurkat cells by U937 macrophages. Moreover, the phagocytosis of PS exposing, activated platelets by human blood derived monocytes declined in the presence of PCI. In U937 cells the expression of PCI as well as the surface binding of PCI increased with time of phorbol ester treatment/macrophage differentiation. The results of this study suggest a role of PCI not only for the function and/or maturation of macrophages, but also as a negative regulator of apoptotic cell and activated platelets removal. PMID:25000564

CD147 induces up-regulation of vascular endothelial growth factor in U937-derived foam cells through PI3K/AKT pathway.

PubMed

Zong, JiaXin; Li, YunTian; Du, DaYong; Liu, Yang; Yin, YongJun

2016-11-01

Intraplaque angiogenesis has been recognized as an important risk factor for the rupture of advanced atherosclerotic plaques in recent years. CD147, also called Extracellular Matrix Metalloproteinase Inducer, has been found the ability to promote angiogenesis in many pathological conditions such as cancer diseases and rheumatoid arthritis via the up-regulation of vascular endothelial growth factor (VEGF), a critical mediator of angiogenesis. We investigated whether CD147 would also induce the up-regulation of VEGF in the foam cells formation process and explored the probable signaling pathway. The results showed the expression of CD147 and VEGF was significantly higher in U937-derived foam cells. After CD147 stealth siRNA transfection treatment, the production of VEGF was reduced depended on the inhibition efficiency of CD147 siRNAs.The special signaling pathway inhibitors LY294002, SP600125, SB203580 and U0126 were added to cultures respectively and the results showed LY294002 dose-dependently inhibited the expression of VEGF. The reduction of phospho-Akt was observed in both LY294002 and siRNA groups, suggested that the phosphatidylinositol 3-kinase/Akt pathway may be the probable signaling pathway underlying CD147 induced up-regulation of VEGF in U937-derived foam cells. Copyright © 2016 Elsevier Inc. All rights reserved.

miR-223 is upregulated in monocytes from patients with tuberculosis and regulates function of monocyte-derived macrophages.

PubMed

Liu, Yanhua; Wang, Ruo; Jiang, Jing; Yang, Bingfen; Cao, Zhihong; Cheng, Xiaoxing

2015-10-01

Tuberculosis (TB) is a serious infectious disease that most commonly affects the lungs. Macrophages are among the first line defenders against establishment of Mycobacterium tuberculosis infection in the lungs. In this study, we found that activation and cytokine production in monocyte-derived macrophages (MDM) from patients with active TB was impaired. miR-223 expression was significantly elevated in monocytes and MDM from patients with TB compared with healthy controls. To determine the functional role of miR-223 in macrophages, stable miR-223-expressing and miR-223 antisense-expressing U937 cells were established. Compared with empty vector controls, expression of IL-1β, IL-6, TNF-α and IL-12p40 genes was significantly higher in miR-223 antisense-expressing U937 cells, but lower in miR-223-expressing U937 cells. miR-223 can negatively regulate activation of NF-κB by inhibition of p65 phosphorylation and nuclear translocation. It is concluded that miR-223 can regulate macrophage function by inhibition of cytokine production and NF-κB activation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Recombinant latcripin 11 of Lentinula edodes C91-3 suppresses the proliferation of various cancer cells.

PubMed

Gao, Yifan; Padhiar, Arshad Ahmed; Wang, Jia; Zhang, Wei; Zhong, Mintao; Liu, Ben; Kang, Zhijie; Wang, Xiaoli; Li, Xingyun; Huang, Min

2018-02-05

Lentinula edodes C91-3 is an edible mushroom that has demonstrated a remarkable anti-tumor effect in various cancer cells both in vitro and in vivo. In the present study, we report the ability of recombinant thioredoxin-like latcripin 11 (LP-11) of Lentinula edodes C91-3 to suppress the proliferation of various cancer cells. The LP-11 gene of Lentinula edodes C91-3 was cloned in the pET-32a(+) expression vector and expressed in a prokaryotic system. The expressed protein was refolded by gradual dialysis and purified by affinity gel filtration chromatography. The antioxidant activity of LP-11 was tested by 1,1-dipheny l-2-picrylhydrazyl (DPPH) assay. The anti-tumor activity of recombinant LP-11 was tested in eight kinds of tumor cell lines by CCK-8 assay. Recombinant LP-11 significantly suppressed the proliferation of various cancer cells, but not normal human umbilical vein endothelial cells. Human lymphoma U937 cells exhibited the most sensitivity to LP-11 protein. U937 cell apoptosis was assessed by Annexin V staining coupled with flow cytometry, and mitochondrial morphology was analyzed by light and electron microscopy. It was revealed that recombinant LP-11 induced apoptosis in human leukemic monocyte lymphoma U937 cells. Our findings suggest that recombinant LP-11 is a promising agent for the treatment of lymphoma. Copyright © 2017. Published by Elsevier B.V.

The targeted inhibition of mitochondrial Hsp90 overcomes the apoptosis resistance conferred by Bcl-2 in Hep3B cells via necroptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Chunlan; Department of Physiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058; Oh, Joon Seok

Previous studies have reported that a Gamitrinib variant containing triphenylphosphonium (G-TPP) binds to mitochondrial Hsp90 and rapidly inhibits its activity, thus inducing the apoptotic pathway in the cells. Accordingly, G-TPP shows a potential as a promising drug for the treatment of cancer. A cell can die from different types of cell death such as apoptosis, necrosis, necroptosis, and autophagic cell death. In this study, we further investigated the mechanisms and modes of cell death in the G-TPP-treated Hep3B and U937 cell lines. We discovered that G-TPP kills the U937 cells through the apoptotic pathway and the overexpression of Bcl-2 significantlymore » inhibits U937 cell death to G-TPP. We further discovered that G-TPP kills the Hep3B cells by activating necroptosis in combination with the partial activation of caspase-dependent apoptosis. Importantly, G-TPP overcomes the apoptosis resistance conferred by Bcl-2 in Hep3B cells via necroptosis. We also observed that G-TPP induces compensatory autophagy in the Hep3B cell line. We further found that whereas there is a Bcl-2-Beclin 1 interaction in response to G-TPP, silencing the beclin 1 gene failed to block LC3-II accumulation in the Hep3B cells, indicating that G-TPP triggers Beclin 1-independent protective autophagy in Hep3B cells. Taken together, these data reveal that G-TPP induces cell death through a combination of death pathways, including necroptosis and apoptosis, and overcomes the apoptosis resistance conferred by Bcl-2 in Hep3B cells via necroptosis. These findings are important for the therapeutic exploitation of necroptosis as an alternative cell death program to bypass the resistance to apoptosis. Highlights: ► G-TPP binds to mitochondrial Hsp90. ► G-TPP induces apoptosis in U937 human leukemia cancer cells. ► G-TPP induces combination of death pathways in Hep3B cell. ► G-TPP overcomes the resistance conferred by Bcl-2 in Hep3B cells via necroptosis. ► G-TPP triggers Beclin 1-independent protective autophagy in Hep3B cells.« less

Staurosporine induces rapid homotypic intercellular adhesion of U937 cells via multiple kinase activation

PubMed Central

Cho, Jae Youl; Katz, David R; Chain, Benjamin M

2003-01-01

Staurosporine is a broad-specificity kinase inhibitor, which has acted as lead compound for the development of some novel cytotoxic compounds for treatment of cancer. This study investigates the unexpected observation that staurosporine can also induce homotypic cellular aggregation. In this study, staurosporine is shown to activate rapid homotypic aggregation of U937 cells, at concentrations below those required to induce cell death. This activity is a particular feature of staurosporine, and is not shared by a number of other kinase inhibitors. The proaggregating activity of staurosporine is inhibited by deoxyglucose, cytochalasin B and colchicine. Staurosporine-induced aggregation can be distinguished from that induced by the phorbol 12-myristate 13-acetate by faster kinetics and insensitivity to cycloheximide. Staurosporine induces translocation of conventional and novel, but not atypical isoforms of protein kinase C (PKC). Aggregation induced by staurosporine is inhibited by a number of inhibitors of PKC isoforms, and by inhibitors of protein tyrosine kinases. Staurosporine also induces rapid phosphorylation of ERK and p38, and inhibitors of both these enzymes block aggregation. Staurosporine induces dysregulated activation of multiple kinase signaling pathways in U937 cells, and the combined activity of several of these pathways is essential for the induction of aggregation. PMID:12970105

Antiproliferative Cardenolide Glycosides of Elaeodendron alluaudianum from the Madagascar Rainforest1

PubMed Central

Hou, Yanpeng; Cao, Shugeng; Brodie, Peggy; Callmander, Martin; Ratovoson, Fidisoa; Randrianaivo, Richard; Rakotobe, Etienne; Rasamison, Vincent E.; Rakotonandrasana, Stephan; TenDyke, Karen; Suh, Edward M.; Kingston, David G. I.

2010-01-01

Bioassay-guided fractionation of an ethanol extract of a Madagascar collection of Elaeodendron alluaudianum led to the isolation of two new cardenolide glycosides (1 and 2). The 1H and 13C NMR spectra of both compounds were fully assigned using a combination of 2D NMR experiments, including 1H-1H COSY, HSQC, HMBC, and ROESY sequences. Both compounds 1 and 2 were tested against the A2780 human ovarian cancer cell line and the U937 human histiocytic lymphoma cell line assays, and showed significant antiproliferative activity with IC50 values of 0.12 and 0.07 μM against the A2780 human ovarian cancer cell line, and 0.15 and 0.08 μM against the U937 human histiocytic lymphoma cell line, respectively. PMID:19058971

Matrix metalloproteinase-2 and -9 are induced differently by metal nanoparticles in human monocytes: The role of oxidative stress and protein tyrosine kinase activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan Rong; Department of Pathology, Fujian Medical University, Fujian; Mo Yiqun

2008-12-01

Recently, many studies have shown that nanoparticles can translocate from the lungs to the circulatory system. As a particulate foreign body, nanoparticles could induce host responses such as reactive oxygen species (ROS) generation, inflammatory cytokine and matrix metalloproteinase (MMP) release which play a major role in tissue destruction and remodeling. However, the direct effects of nanoparticles on leukocytes, especially monocytes, are still unclear. The objective of the present study was to compare the ability of Nano-Co and Nano-TiO{sub 2} to cause alteration of transcription and activity of MMPs and to explore possible mechanisms. We hypothesized that non-toxic doses of somemore » transition metal nanoparticles stimulate an imbalance of MMP/TIMP that cause MMP production that may contribute to their health effects. To test this hypothesis, U937 cells were treated with Nano-Co and Nano-TiO{sub 2} and cytotoxic effects and ROS generation were measured. The alteration of MMP-2 and MMP-9 expression and activity of MMP-2 and MMP-9 after exposure to these metal nanoparticles were subsequently determined. To investigate the potential signaling pathways involved in the Nano-Co-induced MMP activation, the ROS scavengers or inhibitors, AP-1 inhibitor, and protein tyrosine kinase (PTK) inhibitors were also used to pre-treat U937 cells. Our results demonstrated that exposure of U937 cells to Nano-Co, but not to Nano-TiO{sub 2}, at a dose that does not cause cytotoxicity, resulted in ROS generation and up-regulation of MMP-2 and MMP-9 mRNA expression{sub ..} Our results also showed dose- and time-related increases in pro-MMP-2 and pro-MMP-9 gelatinolytic activities in conditioned media after exposure of U937 cells to Nano-Co, but not to Nano-TiO{sub 2}. Nano-Co-induced pro-MMP-2 and pro-MMP-9 activity increases were inhibited by pre-treatment with ROS scavengers or inhibitors. We also demonstrated dose- and time-related decreases in tissue inhibitors of metalloproteinases 2 (TIMP-2) in U937 cells after exposure to Nano-Co, but not to Nano-TiO{sub 2}. However, neither Nano-Co nor Nano-TiO{sub 2} exposure led to any transcriptional change of TIMP-1. The decrease of TIMP-2 after exposure to Nano-Co was also inhibited by pre-treatment with ROS scavengers or inhibitors. Our results also showed that pre-treatment of U937 cells with AP-1 inhibitor, curcumin, or the PTK specific inhibitor, herbimycin A or genistein, prior to exposure to Nano-Co, significantly abolished Nano-Co-induced pro-MMP-2 and-9 activity. Our results suggest that Nano-Co causes an imbalance between the expression and activity of MMPs and their inhibitors which is mediated by the AP-1 and tyrosine kinase pathways due to oxidative stress.« less

Role of monocyte-lineage cells in prostate cancer cell invasion and tissue factor expression.

PubMed

Lindholm, Paul F; Lu, Yi; Adley, Brian P; Vladislav, Tudor; Jovanovic, Borko; Sivapurapu, Neela; Yang, Ximing J; Kajdacsy-Balla, André

2010-11-01

Tissue factor (TF) is a cell surface glycoprotein intricately related to blood coagulation and inflammation. This study was performed to investigate the role of monocyte-lineage cells in prostate cancer cell TF expression and cell invasion. Prostate cancer cell invasion was tested with and without added peripheral blood monocytes or human monocyte-lineage cell lines. TF neutralizing antibodies were used to determine the TF requirement for prostate cancer cell invasion activity. Immunohistochemistry was performed to identify prostate tissue CD68 positive monocyte-derived cells and prostate epithelial TF expression. Co-culture of PC-3, DU145, and LNCaP cells with isolated human monocytes significantly stimulated prostate cancer cell invasion activity. TF expression was greater in highly invasive prostate cancer cells and was induced in PC-3, DU145, and LNCaP cells by co-culture with U-937 cells, but not with THP-1 cells. TF neutralizing antibodies inhibited PC-3 cell invasion in co-cultures with monocyte-lineage U-937 or THP-1 cells. Prostate cancer tissues contained more CD68 positive cells in the stroma and epithelium (145 ± 53/mm(2)) than benign prostate (108 ± 31/mm(2)). Samples from advanced stage prostate cancer tended to contain more CD68 positive cells when compared with lower stage lesions. Prostatic adenocarcinoma demonstrated significantly increased TF expression compared with benign prostatic epithelium. This study shows that co-culture with monocyte-lineage cells induced prostate cancer cell invasion activity. PC-3 invasion and TF expression was induced in co-culture with U-937 cells and partially inhibited with TF neutralizing antibodies.

Symptoms of adult chronic and acute leukaemia before diagnosis: large primary care case-control studies using electronic records

PubMed Central

Shephard, Elizabeth A; Neal, Richard D; Rose, Peter W; Walter, Fiona M; Hamilton, Willie

2016-01-01

Background Leukaemia is the eleventh commonest UK cancer. The four main subtypes have different clinical profiles, particularly between chronic and acute types. Aim To identify the symptom profiles of chronic and acute leukaemia in adults in primary care. Design and setting Matched case-control studies using Clinical Practice Research Datalink records. Method Putative symptoms of leukaemia were identified in the year before diagnosis. Conditional logistic regression was used for analysis, and positive predictive values (PPVs) were calculated to estimate risk. Results Of cases diagnosed between 2000 and 2009, 4655 were aged ≥40 years (2877 chronic leukaemia (CL), 937 acute leukaemia (AL), 841 unreported subtype). Ten symptoms were independently associated with CL, the three strongest being: lymphadenopathy (odds ratio [OR] 22, 95% confidence interval [CI] = 13 to 36), weight loss (OR 3.0, 95% CI = 2.1 to 4.2), and bruising (OR 2.3, 95% CI = 1.6 to 3.2). Thirteen symptoms were independently associated with AL, the three strongest being: nosebleeds and/or bleeding gums (OR 5.7, 95% CI = 3.1 to 10), fever (OR 5.3, 95% CI = 2.7 to 10), and fatigue (OR 4.4, 95% CI = 3.3 to 6.0). No individual symptom or combination of symptoms had a PPV >1%. Conclusion The symptom profiles of CL and AL have both overlapping and distinct features. This presents a dichotomy for GPs: diagnosis, by performing a full blood count, is easy; however, the symptoms of leukaemia are non-specific and of relatively low risk. This explains why many leukaemia diagnoses are unexpected findings. PMID:26917658

Effects of an inhibitor of tripeptidyl peptidase II (Ala-Ala-Phe-chloromethylketone) and its combination with an inhibitor of the chymotrypsin-like activity of the proteasome (PSI) on apoptosis, cell cycle and proteasome activity in U937 cells.

PubMed

Bury, M; Młynarczuk, I; Pleban, E; Hoser, G; Kawiak, J; Wójcik, C

2001-01-01

AAF-AMC is not a specific TPP II substrate, since it is also hydrolyzed by purified proteasomes. Moreover, AAF-cmk, claimed to be a specific TPP II inhibitor, also inhibits the chymotrypsin-like activity of the proteasome. While AAF-cmk itself is mildly cytostatic to U-937 cells and induces cell cycle block in G1, its combination with PSI does not induce an increase in the cytostatic/cytotoxic effects. This suggests that TPP II is possibly less important for cell metabolism than it was previously believed and it is less probable that it can be able to fully compensate for the loss of the proteasome function.

Altered Regulation of ELAVL1/HuR in HLA-B27–Expressing U937 Monocytic Cells

PubMed Central

Sahlberg, Anna S.; Ruuska, Marja; Granfors, Kaisa; Penttinen, Markus A.

2013-01-01

Objective To investigate the role of HLA-B27 expression in the regulation of RNA binding protein (RBP) Embryonic Lethal Abnormal Vision (ELAV) L1/Human antigen R (HuR) expression in Salmonella-infected or LPS-stimulated human monocytic cells, since HuR is a critical regulator of the post-transcriptional fate of many genes (e.g. TNFα) important in inflammatory response. Methods U937 monocytic cells were stably transfected with pSV2neo resistant vector (mock), wild type HLA–B27, or mutated HLA–B27 with amino acid substitutions in the B pocket. Cells were differentiated, infected with Salmonella enteritidis or stimulated with lipopolysaccharide. The expression levels of HuR protein and cleavage products (CP1 and CP2) were detected by Western blotting and flow cytometry. Specific inhibitors were used to study the role of PKR and p38 in HuR expression and generation of CPs. TNFα and IL-10 secretion after p38 and PKR inhibition were measured by ELISA. Results Full length HuR is overexpressed and HuR cleavage is disturbed in U937 monocytic cells expressing HLA-B27 heavy chains (HC). Increased full length HuR expression, disturbed cleavage and reduced dependence on PKR after infection correlate with the expression of glutamic acid 45 in the B pocket that is linked to the misfolding of HLA-B27. Conclusion Results show that the expression of HLA-B27 HCs modulates the intracellular environment of U937 monocyte/macrophages by altering HuR regulation. This phenomenon is at least partly dependent on the misfolding feature of the B27 molecule. Since HuR is an important regulator of multiple genes involved in inflammatory response observations offer an explanation how HLA-B27 may modulate inflammatory response. PMID:23894643

Differential changes in sphingolipids between TNF-induced necroptosis and apoptosis in U937 cells and necroptosis-resistant sublines.

PubMed

Sawai, Hirofumi; Ogiso, Hideo; Okazaki, Toshiro

2015-09-01

Differential changes in various sphingolipids between TNF-induced necroptosis and apoptosis were investigated using liquid chromatography-tandem mass spectrometry. A marked increase in d18:1/16:0 ceramide was detected in U937 cells treated with TNF in the presence of Z-VAD-fmk (VAD). The level of d18:1/16:0 ceramide in necroptosis was almost twice as high as that in apoptosis after 4h, while an increase in PI-positive cells was observed only in necroptosis within 4h. Necroptosis-resistant U937 (UNR) sublines were established to more clearly discriminate between necroptosis and apoptosis. All three UNR sublines were almost completely resistant to the treatment with TNF/VAD, but were as sensitive to TNF-induced apoptosis as parental cells. The expression of RIP3, a pivotal kinase in necroptosis, was lost in all three UNR sublines. In contrast with the large increase in ceramide levels in TNF/VAD-treated parental cells, they were only slightly increased in UNR cells. Although intracellular levels of reactive oxygen species (ROS) were elevated in both necroptosis and apoptosis, the treatment with butylated hydroxyanisole, an antioxidant, significantly inhibited increases in ceramide levels and PI-positive cells only in necroptosis. These results implicate that the ROS-induced large increase in ceramide levels may play a role in plasma membrane permeabilization in TNF-induced necroptosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of the cytotoxicity of clinically relevant cobalt-chromium and alumina ceramic wear particles in vitro.

PubMed

Germain, M A; Hatton, A; Williams, S; Matthews, J B; Stone, M H; Fisher, J; Ingham, E

2003-02-01

Concern over polyethylene wear particle induced aseptic loosening of metal-on-polyethylene hip prostheses has led to renewed interest in alternative materials such as metal-on-metal and alumina ceramic-on-alumina ceramic for total hip replacement. This study compared the effects of clinically relevant cobalt-chromium and alumina ceramic wear particles on the viability of U937 histiocytes and L929 fibroblasts in vitro. Clinically relevant cobalt-chromium wear particles were generated using a flat pin-on-plate tribometer. The mean size of the clinically relevant metal particles was 29.5+/-6.3 nm (range 5-200 nm). Clinically relevant alumina ceramic particles were generated in the Leeds MkII anatomical hip simulator from a Mittelmieier prosthesis using micro-separation motion. This produced particles with a bimodal size distribution. The majority (98%) of the clinically relevant alumina ceramic wear debris was 5-20 nm in size. The cytotoxicity of the clinically relevant wear particles was compared to commercially available cobalt-chromium (9.87 microm+/-5.67) and alumina ceramic (0.503+/-0.19 microm) particles. The effects of the particles on the cells over a 5 day period at different particle volume (microm(3)) to cell number ratios were tested and viability determined using ATP-Lite(TM). Clinically relevant cobalt-chromium particles 50 and 5 microm(3) per cell reduced the viability of U937 cells by 97% and 42% and reduced the viability of L929 cells by 95% and 73%, respectively. At 50 microm(3) per cell, the clinically relevant ceramic particles reduced U937 cell viability by 18%. None of the other concentrations of the clinically relevant particles were toxic. The commercial cobalt-chromium and alumina particles did not affect the viability of either the U937 histiocytes or the L929 fibroblasts.Thus at equivalent particle volumes the clinically relevant cobalt-chromium particles were more toxic then the alumina ceramic particles. This study has emphasised the fact that the nature, size and volume of particles are important in assessing biological effects of wear debris on cells in vitro.

DIFFERENCES IN ARACHIDONIC ACID METABOLISM BY HUMAN MYELOMONCYTIC CELL LINES

EPA Science Inventory

The production of arachidonic acid metabolites by the HL60, ML3, and U937 human phagocyte cell lines were determined after incubation with interferongamma (IFNg; 500 U/ml) or vehicle for 4 days. ells were prelabeled with tritiated arachidonic acid for 4 hours, and media supernata...

Urokinase receptor and CXCR4 are regulated by common microRNAs in leukaemia cells

PubMed Central

Alfano, Daniela; Gorrasi, Anna; Li Santi, Anna; Ricci, Patrizia; Montuori, Nunzia; Selleri, Carmine; Ragno, Pia

2015-01-01

The urokinase-type plasminogen activator (uPA) receptor (uPAR) focuses uPA proteolytic activity on the cell membrane, promoting localized degradation of extracellular matrix (ECM), and binds vitronectin (VN), mediating cell adhesion to the ECM. uPAR-bound uPA and VN induce proteolysis-independent intracellular signalling, regulating cell adhesion, migration, survival and proliferation. uPAR cross-talks with CXCR4, the receptor for the stroma-derived factor 1 chemokine. CXCR4 is crucial in the trafficking of hematopoietic stem cells from/to the bone marrow, which involves also uPAR. Both uPAR and CXCR4 are expressed in acute myeloid leukaemia (AML), with a lower expression in undifferentiated and myeloid subsets, and higher expression in myelomonocytic and promyelocytic subsets. We hypothesized a microRNA (miR)-mediated co-regulation of uPAR and CXCR4 expression, which could allow their cross-talk at the cell surface. We identified three miRs, miR-146a, miR-335 and miR-622, regulating the expression of both uPAR and CXCR4 in AML cell lines. Indeed, these miRs directly target the 3′untranslated region of both uPAR- and CXCR4-mRNAs; accordingly, uPAR/CXCR4 expression is reduced by their overexpression in AML cells and increased by their specific inhibitors. Overexpression of all three miRs impairs migration, invasion and proliferation of myelomonocytic cells. Interestingly, we observed an inverse relationship between uPAR/CXCR4 expression and miR-146a and miR-335 levels in AML blasts, suggesting their possible role in the regulation of uPAR/CXCR4 expression also in vivo. PMID:26082201

Urokinase–urokinase receptor interaction mediates an inhibitory signal for HIV-1 replication

PubMed Central

Alfano, Massimo; Sidenius, Nicolai; Panzeri, Barbara; Blasi, Francesco; Poli, Guido

2002-01-01

Elevated levels of soluble urokinase-type plasminogen activator (uPA) receptor, CD87/u-PAR, predict survival in individuals infected with HIV-1. Here, we report that pro-uPA (or uPA) inhibits HIV-1 expression in U937-derived chronically infected promonocytic U1 cells stimulated with phorbol 12-myristate 13-acetate (PMA) or tumor necrosis factor-α (TNF-α). However, pro-uPA did not inhibit PMA or TNF-α-dependent activation of nuclear factor-kB or activation protein-1 in U1 cells. Cell-associated HIV protein synthesis also was not decreased by pro-uPA, although the release of virion-associated reverse transcriptase activity was substantially inhibited, suggesting a functional analogy between pro-uPA and the antiviral effects of IFNs. Indeed, cell disruption reversed the inhibitory effect of pro-uPA on activated U1 cells, and ultrastructural analysis confirmed that virions were preferentially retained within cell vacuoles in pro-uPA treated cells. Neither expression of endogenous IFNs nor activation of the IFN-inducible Janus kinase/signal transducer and activator of transcription pathway were induced by pro-uPA. Pro-uPA also inhibited acute HIV replication in monocyte-derived macrophages and activated peripheral blood mononuclear cells, although with great inter-donor variability. However, pro-uPA inhibited HIV replication in acutely infected promonocytic U937 cells and in ex vivo cultures of lymphoid tissue infected in vitro. Because these effects occurred at concentrations substantially lower than those affecting thrombolysis, pro-uPA may represent a previously uncharacterized class of antiviral agents mimicking IFNs in their inhibitory effects on HIV expression and replication. PMID:12084931

Molecular mechanisms of apoptosis induction by 2-dodecylcyclobutanone, a radiolytic product of palmitic acid, in human lymphoma U937 cells.

PubMed

Yu, Da-Yong; Zhao, Qing-Li; Furuta, Masakazu; Todoriki, Setsuko; Izumi, Keisuke; Yamakage, Kohji; Matsumoto, Kozo; Nomura, Takaharu; Kondo, Takashi

2012-06-01

The irradiation of fat-containing food forms 2-dodecylcyclobutanone (2-DCB) from palmitic acid (PA). In this study, we investigated whether 2-DCB and PA induce apoptosis in human lymphoma U937 cells. We found that cell viability decreased by 2-DCB and apoptosis was induced by 2-DCB and PA. 2-DCB and PA significantly enhanced the formation of intracellular reactive oxygen species (ROS). Apoptosis induced by 2-DCB and PA was strongly prevented by an antioxidant, N-acetyl-L: -cysteine. The treatment with 2-DCB and PA resulted in the loss of mitochondrial membrane potential, and Fas, caspase-8 and caspase-3 activation. Pretreatment with a pan-caspase inhibitor (z-VAD) significantly inhibited apoptosis induced by 2-DCB and PA. Moreover, 2-DCB and PA also induced Bax up-regulation, the reduction in Bcl-2 expression level, Bid cleavage and the release of cytochrome c from the mitochondria to the cytosol. In addition, an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) was observed after the treatment with 2-DCB and PA. Our results indicated that intracellular ROS generation, the modulation of the Fas-mitochondrion-caspase-dependent pathway and the increase in [Ca(2+)](i) involved in apoptosis are induced by 2-DCB and PA in U937 cells.

SIRT6 Is a Positive Regulator of Aldose Reductase Expression in U937 and HeLa cells under Osmotic Stress: In Vitro and In Silico Insights

PubMed Central

Timucin, Ahmet Can; Basaga, Huveyda

2016-01-01

SIRT6 is a protein deacetylase, involved in various intracellular processes including suppression of glycolysis and DNA repair. Aldose Reductase (AR), first enzyme of polyol pathway, was proposed to be indirectly associated to these SIRT6 linked processes. Despite these associations, presence of SIRT6 based regulation of AR still remains ambiguous. Thus, regulation of AR expression by SIRT6 was investigated under hyperosmotic stress. A unique model of osmotic stress in U937 cells was used to demonstrate the presence of a potential link between SIRT6 and AR expression. By overexpressing SIRT6 in HeLa cells under hyperosmotic stress, its role on upregulation of AR was revealed. In parallel, increased SIRT6 activity was shown to upregulate AR in U937 cells under hyperosmotic milieu by using pharmacological modulators. Since these modulators also target SIRT1, binding of the inhibitor, Ex-527, specifically to SIRT6 was analyzed in silico. Computational observations indicated that Ex-527 may also target SIRT6 active site residues under high salt concentration, thus, validating in vitro findings. Based on these evidences, a novel regulatory step by SIRT6, modifying AR expression under hyperosmotic stress was presented and its possible interactions with intracellular machinery was discussed. PMID:27536992

In vitro cytotoxic activity evaluation of phenytoin derivatives against human leukemia cells.

PubMed

Śladowska, Katarzyna; Handzlik, Jadwiga; Kieć-Kononowicz, Katarzyna; Mazur, Lidia

2016-09-01

Hydantoin derivatives, including phenytoin (5,5-diphenylhydantoin), have recently gained attention as they possess a variety of important biochemical and pharmacological properties. Nevertheless, available information on anticancer activity of hydantoin derivatives is still scarce. Here, we evaluated possible antileukemic potential of four phenytoin analogs, namely: methyl 2-(2,4-dioxo-5,5-diphenylimidazolidin-3-yl)propanoate (1), methyl 2-(1-(3-bromopropyl)-2,4-dioxo-5,5-diphenylimidazolidin-3-yl)propanoate (2), 1-(3-bromopropyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (3) and 1-(3-bromobutyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (4). The experiments were performed on human acute histiocytic lymphoma U937 cells and human promyelocytic leukemia HL-60 cells. The present study was conducted using spectrophotometric 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay and the electronic Beckman-Coulter method. We observed temporary changes in the leukemia cell viability, volume and count. The effects of the four 5,5-diphenylhydantoin derivatives on U937 and HL-60 cells depended on the agent tested and its concentration, the time intervals after the compound application, and the leukemia cell line used. HL-60 cells were more sensitive than U937 cells to the action of the phenytoin analogs (1-4). The antileukemic activities of the three bromoalkyl diphenylhydantoin derivatives (2, 3, and 4) were stronger than that of the compound 1 [methyl 2-(2,4-dioxo-5,5-diphenylimidazolidin-3-yl) propanoate], with no bromoalkyl substituent. The structural modifications of 5,5-diphenylhydantoin are responsible for such varied antileukemic potential of its four derivatives.

Distinct MAPK signaling pathways, p21 up-regulation and caspase-mediated p21 cleavage establishes the fate of U937 cells exposed to 3-hydrogenkwadaphnin: Differentiation versus apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moosavi, Mohammad Amin; Yazdanparast, Razieh

2008-07-01

Despite the depth of knowledge concerning the pathogenesis of acute myeloblastic leukemia (AML), long-term survival remains unresolved. Therefore, new agents that act more selectively and more potently are required. In that line, we have recently characterized a novel diterpene ester, called 3-hydrogenkwadaphnin (3-HK), with capability to induce both differentiation and apoptosis in various leukemia cell lines. These effects of 3-HK were mediated through inhibition of inosine 5'-monophosphate dehydrogenase, a selective up-regulated enzyme in cancerous cells, especially leukemia. However, it remains elusive to understand how cells display different fates in response to 3-HK. Here, we report the distinct molecular signaling pathwaysmore » involved in forcing of 3-HK-treated U937 cells to undergo differentiation and apoptosis. After 3-HK (15 nM) treatment, a portion of U937 cells adhered to the culture plates and showed macrophage criteria while others remained in suspension and underwent apoptosis. The differentiated cells arrested in G{sub 0}/G{sub 1} phase of cell cycle and showed early activation of ERK1/2 pathway (3 h) along with ERK-dependent p21{sup Cip/WAF1} (p21) up-regulation and expression of p27{sup Kip1} and Bcl-2. In contrast, the suspension cells underwent apoptosis through Fas/FasL and mitochondrial pathways. The occurrence of apoptosis in these cells were accompanied with caspase-8-mediated p21 cleavage and delayed activation (24 h) of JNK1/2 and p38 MAPK. Taken together, these results suggest that distinct signaling pathways play a pivotal role in fates of drug-treated leukemia cells, thus this may pave some novel therapeutical utilities.« less

Regulation of CD93 cell surface expression by protein kinase C isoenzymes.

PubMed

Ikewaki, Nobunao; Kulski, Jerzy K; Inoko, Hidetoshi

2006-01-01

Human CD93, also known as complement protein 1, q subcomponent, receptor (C1qRp), is selectively expressed by cells with a myeloid lineage, endothelial cells, platelets, and microglia and was originally reported to be involved in the complement protein 1, q subcomponent (C1q)-mediated enhancement of phagocytosis. The intracellular molecular events responsible for the regulation of its expression on the cell surface, however, have not been determined. In this study, the effect of protein kinases in the regulation of CD93 expression on the cell surface of a human monocyte-like cell line (U937), a human NK-like cell line (KHYG-1), and a human umbilical vein endothelial cell line (HUV-EC-C) was investigated using four types of protein kinase inhibitors, the classical protein kinase C (cPKC) inhibitor Go6976, the novel PKC (nPKC) inhibitor Rottlerin, the protein kinase A (PKA) inhibitor H-89 and the protein tyrosine kinase (PTK) inhibitor herbimycin A at their optimum concentrations for 24 hr. CD93 expression was analyzed using flow cytometry and glutaraldehyde-fixed cellular enzyme-linked immunoassay (EIA) techniques utilizing a CD93 monoclonal antibody (mAb), mNI-11, that was originally established in our laboratory as a CD93 detection probe. The nPKC inhibitor Rottlerin strongly down-regulated CD93 expression on the U937 cells in a dose-dependent manner, whereas the other inhibitors had little or no effect. CD93 expression was down-regulated by Go6976, but not by Rottlerin, in the KHYG-1 cells and by both Rottlerin and Go6976 in the HUV-EC-C cells. The PKC stimulator, phorbol myristate acetate (PMA), strongly up-regulated CD93 expression on the cell surface of all three cell-lines and induced interleukin-8 (IL-8) production by the U937 cells and interferon-gamma (IFN-gamma) production by the KHYG-1 cells. In addition, both Go6976 and Rottlerin inhibited the up-regulation of CD93 expression induced by PMA and IL-8 or IFN-gamma production in the respective cell-lines. Whereas recombinant tumor necrosis factor-alpha (rTNF-alpha) slightly up-regulated CD93 expression on the U937 cells, recombinant interleukin-1beta (rIL-1beta), recombinant interleukin-2 (rIL-2), recombinant interferon-gamma (rIFN-gamma) and lipopolysaccharide (LPS) had no effect. Taken together, these findings indicate that the regulation of CD93 expression on these cells involves the PKC isoenzymes.

Hyperforin inhibits Akt1 kinase activity and promotes caspase-mediated apoptosis involving Bad and Noxa activation in human myeloid tumor cells.

PubMed

Merhi, Faten; Tang, Ruoping; Piedfer, Marion; Mathieu, Julie; Bombarda, Isabelle; Zaher, Murhaf; Kolb, Jean-Pierre; Billard, Christian; Bauvois, Brigitte

2011-01-01

The natural phloroglucinol hyperforin HF displays anti-inflammatory and anti-tumoral properties of potential pharmacological interest. Acute myeloid leukemia (AML) cells abnormally proliferate and escape apoptosis. Herein, the effects and mechanisms of purified HF on AML cell dysfunction were investigated in AML cell lines defining distinct AML subfamilies and primary AML cells cultured ex vivo. HF inhibited in a time- and concentration-dependent manner the growth of AML cell lines (U937, OCI-AML3, NB4, HL-60) by inducing apoptosis as evidenced by accumulation of sub-G1 population, phosphatidylserine externalization and DNA fragmentation. HF also induced apoptosis in primary AML blasts, whereas normal blood cells were not affected. The apoptotic process in U937 cells was accompanied by downregulation of anti-apoptotic Bcl-2, upregulation of pro-apoptotic Noxa, mitochondrial membrane depolarization, activation of procaspases and cleavage of the caspase substrate PARP-1. The general caspase inhibitor Z-VAD-fmk and the caspase-9- and -3-specific inhibitors, but not caspase-8 inhibitor, significantly attenuated apoptosis. HF-mediated apoptosis was associated with dephosphorylation of active Akt1 (at Ser(473)) and Akt1 substrate Bad (at Ser(136)) which activates Bad pro-apoptotic function. HF supppressed the kinase activity of Akt1, and combined treatment with the allosteric Akt1 inhibitor Akt-I-VIII significantly enhanced apoptosis of U937 cells. Our data provide new evidence that HF's pro-apoptotic effect in AML cells involved inhibition of Akt1 signaling, mitochondria and Bcl-2 members dysfunctions, and activation of procaspases -9/-3. Combined interruption of mitochondrial and Akt1 pathways by HF may have implications for AML treatment.

Hyperforin Inhibits Akt1 Kinase Activity and Promotes Caspase-Mediated Apoptosis Involving Bad and Noxa Activation in Human Myeloid Tumor Cells

PubMed Central

Merhi, Faten; Tang, Ruoping; Piedfer, Marion; Mathieu, Julie; Bombarda, Isabelle; Zaher, Murhaf; Kolb, Jean-Pierre; Billard, Christian; Bauvois, Brigitte

2011-01-01

Background The natural phloroglucinol hyperforin HF displays anti-inflammatory and anti-tumoral properties of potential pharmacological interest. Acute myeloid leukemia (AML) cells abnormally proliferate and escape apoptosis. Herein, the effects and mechanisms of purified HF on AML cell dysfunction were investigated in AML cell lines defining distinct AML subfamilies and primary AML cells cultured ex vivo. Methodology and Results HF inhibited in a time- and concentration-dependent manner the growth of AML cell lines (U937, OCI-AML3, NB4, HL-60) by inducing apoptosis as evidenced by accumulation of sub-G1 population, phosphatidylserine externalization and DNA fragmentation. HF also induced apoptosis in primary AML blasts, whereas normal blood cells were not affected. The apoptotic process in U937 cells was accompanied by downregulation of anti-apoptotic Bcl-2, upregulation of pro-apoptotic Noxa, mitochondrial membrane depolarization, activation of procaspases and cleavage of the caspase substrate PARP-1. The general caspase inhibitor Z-VAD-fmk and the caspase-9- and -3-specific inhibitors, but not caspase-8 inhibitor, significantly attenuated apoptosis. HF-mediated apoptosis was associated with dephosphorylation of active Akt1 (at Ser473) and Akt1 substrate Bad (at Ser136) which activates Bad pro-apoptotic function. HF supppressed the kinase activity of Akt1, and combined treatment with the allosteric Akt1 inhibitor Akt-I-VIII significantly enhanced apoptosis of U937 cells. Significance Our data provide new evidence that HF's pro-apoptotic effect in AML cells involved inhibition of Akt1 signaling, mitochondria and Bcl-2 members dysfunctions, and activation of procaspases -9/-3. Combined interruption of mitochondrial and Akt1 pathways by HF may have implications for AML treatment. PMID:21998731

Analysis of the HIV-1 LTR NF-kappaB-proximal Sp site III: evidence for cell type-specific gene regulation and viral replication.

PubMed

McAllister, J J; Phillips, D; Millhouse, S; Conner, J; Hogan, T; Ross, H L; Wigdahl, B

2000-09-01

It has been widely demonstrated that the human immunodeficiency virus type 1 (HIV-1) envelope, specifically the V3 loop of the gp120 spike, evolves to facilitate adaptation to different cellular populations within an infected host. Less energy has been directed at determining whether the viral promoter, designated the long terminal repeat (LTR), also exhibits this adaptive quality. Because of the unique nature of the cell populations infected during the course of HIV-1 infection, one might expect the opportunity for such adaptation to exist. This would permit select viral species to take advantage of the different array of conditions and factors influencing transcription within a given cell type. To investigate this hypothesis, the function of natural variants of the NF-kappaB-proximal Sp element (Sp site III) was examined in human cell line models of the two major cell types infected during the natural course of HIV-1 infection, T cells and monocytes. Utilizing the HIV-1 LAI molecular clone, which naturally contains a high-affinity Sp site III, substitution of low-affinity Sp sites in place of the natural site III element markedly decreased viral replication in Jurkat T cells. However, these substitutions had relatively small effects on viral replication in U-937 monocytic cells. Transient transfections of HIV-1 LAI-based LTR-luciferase constructs into these cell lines suggest that the large reduction in viral replication in Jurkat T cells, caused by low-affinity Sp site III variants, may result from reduced basal as well as Vpr- and Tat-activated LTR activities in Jurkat T cells compared to those in U-937 monocytic cells. When the function of Sp site III was examined in the context of HIV-1 YU-2-based LTR-luciferase constructs, substitution of a high-affinity element in place of the natural low-affinity element resulted in increased basal YU-2 LTR activity in Jurkat T cells and reduced activity in U-937 monocytic cells. These observations suggest that recruitment of Sp family members to Sp site III is of greater importance to the function of the viral promoter in the Jurkat T cell line as compared to the U-937 monocytic cell line. These observations also suggest that other regions of the LTR may compensate for Sp recruitment defects in specific cell populations. Copyright 2000 Academic Press.

Activation of Coagulation by Lenalidomide-Based Regimens for the Treatment of Multiple Myeloma

PubMed Central

Isozumi, Yu; Arai, Reina; Fujimoto, Kazumi; Koyama, Takatoshi

2013-01-01

We investigated the procoagulant effects of lenalidomide (Len)-based regimens in vitro focusing on tissue factor (TF) and phosphatidylserine (PS). We examined the effects of a pharmacological concentration of Len with or without the corticosteroid dexamethasone (Dex) and the proteasome inhibitor bortezomib (Bor) using the human vascular endothelial cell line EAhy926 and the monocytic cell lines THP-1 and U937. Cell-surface procoagulant activity (PCA) was induced by Dex-containing regimens in all lines. Expression of TF antigen on the cell surface and of TF mRNA was markedly increased by Dex-containing regimens. PS exposure was increased modestly by a Len-based regimen. PS exposure was increased modestly in EAhy926 cells, and markedly increased in THP-1 and U937 cells by Bor-containing treatment. An anti-TF monoclonal antibody almost completely blocked the induced PCA. When Len is given in combination with Dex, PCA may be induced on endothelial cells and monocytes through TF expression and PS exposure. PMID:23696885

Activation of coagulation by lenalidomide-based regimens for the treatment of multiple myeloma.

PubMed

Isozumi, Yu; Arai, Reina; Fujimoto, Kazumi; Koyama, Takatoshi

2013-01-01

We investigated the procoagulant effects of lenalidomide (Len)-based regimens in vitro focusing on tissue factor (TF) and phosphatidylserine (PS). We examined the effects of a pharmacological concentration of Len with or without the corticosteroid dexamethasone (Dex) and the proteasome inhibitor bortezomib (Bor) using the human vascular endothelial cell line EAhy926 and the monocytic cell lines THP-1 and U937. Cell-surface procoagulant activity (PCA) was induced by Dex-containing regimens in all lines. Expression of TF antigen on the cell surface and of TF mRNA was markedly increased by Dex-containing regimens. PS exposure was increased modestly by a Len-based regimen. PS exposure was increased modestly in EAhy926 cells, and markedly increased in THP-1 and U937 cells by Bor-containing treatment. An anti-TF monoclonal antibody almost completely blocked the induced PCA. When Len is given in combination with Dex, PCA may be induced on endothelial cells and monocytes through TF expression and PS exposure.

Lethality to leukemia cell lines of DNA interstrand cross-links generated by Cloretazine derived alkylating species

PubMed Central

Penketh, Philip G.; Baumann, Raymond P.; Ishiguro, Kimiko; Shyam, Krishnamurthy; Seow, Helen A.; Sartorelli, Alan C.

2010-01-01

Cloretazine [1, 2-bis(methylsulfonyl)-1-(2-chloroethyl)-2-[(methylamino)carbonyl]-hydrazine; VNP40101M; 101M] is a relatively new prodrug with activity in elderly acute myelogenous leukemia patients. Its therapeutic action is due largely to the production of 1-(3-cytosinyl),2-(1-guanyl)ethane cross-links (G-C ethane cross-links) in DNA. The number of cross-links produced in three experimental leukemia lines (L1210, U937 and HL-60) were fewer than 10 per genome at their respective LC50 concentrations. Only 1 in approximately 20,000 90CE molecules produce a cross-link in the AGT (O6-alkylguanine-DNA alkyltransferase) negative L1210 and U937 cell lines and 1 in 400,000 in the AGT positive HL-60 cell line. PMID:18479747

A novel assay system for macrophage-activating factor activity using a human U937 cell line.

PubMed

Ishikawa, Mami; Inoue, Takahiro; Inui, Toshio; Kuchiike, Daisuke; Kubo, Kentaro; Uto, Yoshihiro; Nishikata, Takahito

2014-08-01

Macrophages play important roles in antitumor immunity, and immunotherapy with the group-specific component protein-derived macrophage-activating factor (GcMAF) has been reported to be effective in patients with various types of cancers. However, in macrophage research, it is important to properly evaluate macrophage activity. U937 macrophages were induced by 12-O-tetradecanoyl-13-phorbolacetate (TPA). The phagocytic activity of macrophages was evaluated as the internalized beads ratio. The MAF activity was assessed at 30 min after MAF addition as the activation ratio. We established a novel assay for phagocytic activities using differentiated U937 macrophages. The novel protocol was simple and rapid and was sensitive for GcMAF. This protocol should be useful not only for basic studies, such as those on molecular mechanisms underlying macrophage activation, but also for clinical studies, such as assessment of GcMAF activity prior to clinical use. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Role of ATM in bystander signaling between human monocytes and lung adenocarcinoma cells.

PubMed

Ghosh, Somnath; Ghosh, Anu; Krishna, Malini

2015-12-01

The response of a cell or tissue to ionizing radiation is mediated by direct damage to cellular components and indirect damage mediated by radiolysis of water. Radiation affects both irradiated cells and the surrounding cells and tissues. The radiation-induced bystander effect is defined by the presence of biological effects in cells that were not themselves in the field of irradiation. To establish the contribution of the bystander effect in the survival of the neighboring cells, lung carcinoma A549 cells were exposed to gamma-irradiation, 2Gy. The medium from the irradiated cells was transferred to non-irradiated A549 cells. Irradiated A549 cells as well as non-irradiated A549 cells cultured in the presence of medium from irradiated cells showed decrease in survival and increase in γ-H2AX and p-ATM foci, indicating a bystander effect. Bystander signaling was also observed between different cell types. Phorbol-12-myristate-13-acetate (PMA)-stimulated and gamma-irradiated U937 (human monocyte) cells induced a bystander response in non-irradiated A549 (lung carcinoma) cells as shown by decreased survival and increased γ-H2AX and p-ATM foci. Non-stimulated and/or irradiated U937 cells did not induce such effects in non-irradiated A549 cells. Since ATM protein was activated in irradiated cells as well as bystander cells, it was of interest to understand its role in bystander effect. Suppression of ATM with siRNA in A549 cells completely inhibited bystander effect in bystander A549 cells. On the other hand suppression of ATM with siRNA in PMA stimulated U937 cells caused only a partial inhibition of bystander effect in bystander A549 cells. These results indicate that apart from ATM, some additional factor may be involved in bystander effect between different cell types. Copyright © 2015 Elsevier B.V. All rights reserved.

IRAK-M alters the polarity of macrophages to facilitate the survival of Mycobacterium tuberculosis.

PubMed

Shen, Pei; Li, Quan; Ma, Jilei; Tian, Maopeng; Hong, Fei; Zhai, Xinjie; Li, Jianrong; Huang, Hanju; Shi, Chunwei

2017-08-23

Intracellular bacterium, Mycobacterium tuberculosis (M. tb), infects specifically macrophages as host cells. IRAK-M, a member of IRAK family, is a negative regulator in TLR signaling and specifically expresses in monocytes and macrophages. The role of IRAK-M in intracellular growth of M. tb and macrophage polarization was explored, for deeply understanding the pathogenesis of M. tb, the significance of IRAK-M to innate immunity and pathogen-host interaction. IRAK-M expression was detected in M. tb infected macrophages and in human lung tissue of pulmonary tuberculosis with immunofluorescence staining, Western blot and immunohistochemistry. IRAK-M knock-down and over-expressing cell strains were constructed and intracellular survival of M. tb was investigated by acid-fast staining and colony forming units. Molecular markers of M1-type (pSTAT1 and iNOS) and M2-type (pSTAT6 and Arg-1) macrophages were detected using Western blot in IRAK-M knockdown U937 cells infected with M. tb H37Rv. U937 cells were stimulated with immunostimulant CpG7909 into M1 status and then infected with M. tb H37Rv. Expression of IRAK-M, IRAK-4 and iNOS was detected with immunofluorescence staining and Western blot, to evaluate the effect of IRAK-M to CpG directed M1-type polarization of macrophages during M. tb infection. Molecules related with macrophage's bactericidal ability such as Hif-1 and phosphorylated ERK1/2 were detected with immunohistochemistry and Western blot. IRAK-M increased in M. tb infected macrophage cells and also in human lung tissue of pulmonary tuberculosis. IRAK-M over-expression resulted in higher bacterial load, while IRAK-M interference resulted in lower bacterial load in M. tb infected cells. During M. tb infection, IRAK-M knockdown induced M1-type, while inhibited M2-type polarization of macrophage. M1-type polarization of U937 cells induced by CpG7909 was inhibited by M. tb infection, which was reversed by IRAK-M knockdown in U937 cells. IRAK-M affected Hif-1 and MAPK signaling cascade during M. tb infection. Conclusively, IRAK-M might alter the polarity of macrophages, to facilitate intracellular survival of M. tb and affect Th1-type immunity of the host, which is helpful to understanding the pathogenesis of M. tb.

Association of a murine leukaemia stem cell gene signature based on nucleostemin promoter activity with prognosis of acute myeloid leukaemia in patients.

PubMed

Ali, Mohamed A E; Naka, Kazuhito; Yoshida, Akiyo; Fuse, Kyoko; Kasada, Atsuo; Hoshii, Takayuki; Tadokoro, Yuko; Ueno, Masaya; Ohta, Kumiko; Kobayashi, Masahiko; Takahashi, Chiaki; Hirao, Atsushi

2014-07-18

Acute myeloid leukaemia (AML) is a heterogeneous neoplastic disorder in which a subset of cells function as leukaemia-initiating cells (LICs). In this study, we prospectively evaluated the leukaemia-initiating capacity of AML cells fractionated according to the expression of a nucleolar GTP binding protein, nucleostemin (NS). To monitor NS expression in living AML cells, we generated a mouse AML model in which green fluorescent protein (GFP) is expressed under the control of a region of the NS promoter (NS-GFP). In AML cells, NS-GFP levels were correlated with endogenous NS mRNA. AML cells with the highest expression of NS-GFP were very immature blast-like cells, efficiently formed leukaemia colonies in vitro, and exhibited the highest leukaemia-initiating capacity in vivo. Gene expression profiling analysis revealed that cell cycle regulators and nucleotide metabolism-related genes were highly enriched in a gene set associated with leukaemia-initiating capacity that we termed the 'leukaemia stem cell gene signature'. This gene signature stratified human AML patients into distinct clusters that reflected prognosis, demonstrating that the mouse leukaemia stem cell gene signature is significantly associated with the malignant properties of human AML. Further analyses of gene regulation in leukaemia stem cells could provide novel insights into diagnostic and therapeutic approaches to AML. Copyright © 2014 Elsevier Inc. All rights reserved.

The t(10;11)(p13;q14) in the U937 cell line results in the fusion of the AF10 gene and CALM, encoding a new member of the AP-3 clathrin assembly protein family.

PubMed Central

Dreyling, M H; Martinez-Climent, J A; Zheng, M; Mao, J; Rowley, J D; Bohlander, S K

1996-01-01

The translocation t(10;11)(p13;q14) is a recurring chromosomal abnormality that has been observed in patients with acute lymphoblastic leukemia as well as acute myeloid leukemia. We have recently reported that the monocytic cell line U937 has a t(10;11)(p13;q14) translocation. Using a combination of positional cloning and candidate gene approach, we cloned the breakpoint and were able to show that AF10 is fused to a novel gene that we named CALM (Clathrin Assembly Lymphoid Myeloid leukemia gene) located at 11q14. AF10, a putative transcription factor, had recently been cloned as one of the fusion partners of MLL. CALM has a very high homology in its N-terminal third to the murine ap-3 gene which is one of the clathrin assembly proteins. The N-terminal region of ap-3 has been shown to bind to clathrin and to have a high-affinity binding site for phosphoinositols. The identification of the CALM/AF10 fusion gene in the widely used U937 cell line will contribute to our understanding of the malignant phenotype of this line. Images Fig. 1 Fig. 3 PMID:8643484

Cytotoxicity of Vitex agnus-castus fruit extract and its major component, casticin, correlates with differentiation status in leukemia cell lines.

PubMed

Kikuchi, Hidetomo; Yuan, Bo; Nishimura, Yoshio; Imai, Masahiko; Furutani, Ryota; Kamoi, Saki; Seno, Misako; Fukushima, Shin; Hazama, Shingo; Hirobe, Chieko; Ohyama, Kunio; Hu, Xiao-Mei; Takagi, Norio; Hirano, Toshihiko; Toyoda, Hiroo

2013-12-01

We have demonstrated that an extract from the ripe fruit of Vitex agnus-castus (Vitex) exhibits cytotoxic activities against various types of solid tumor cells, whereas its effects on leukemia cells has not been evaluated to date. In this study, the effects of Vitex and its major component, casticin, on leukemia cell lines, HL-60 and U-937, were investigated by focusing on proliferation, induction of apoptosis and differentiation. Identification and quantitation by NMR spectroscopy showed that casticin accounted for approximate 1% weight of Vitex. Dose-dependent cytotoxicity of Vitex and casticin was observed in both cell lines, and HL-60 cells were more sensitive to the cytotoxicity of Vitex/casticin compared to U-937 cells. Furthermore, compared to unstimulated HL-60 cells, phorbol 12-myristate 13-acetate (PMA)- and 1,25-dihydroxyvitamin D₃ (VD₃)-differentiated HL-60 cells acquired resistance to Vitex/casticin based on the results from cell viability and apoptosis induction analysis. Since the HL-60 cell line is more immature than the U-937 cell line, these results suggested that the levels of cytotoxicity of Vitex/casticin were largely attributed to the degree of differentiation of leukemia cells; that is, cell lines with less differentiated phenotype were more susceptible than the differentiated ones. RT-PCR analysis demonstrated that PMA upregulated the expression of intercellular adhesion molecule-1 (ICAM-1) in HL-60 cells, and that anti-ICAM-1 monoclonal antibody not only abrogated PMA-induced aggregation and adhesion of the cells but also restored its sensitivity to Vitex. These results suggested that ICAM-1 plays a crucial role in the acquired resistance in PMA-differentiated HL-60 cells by contributing to cell adhesion. These findings provide fundamental insights into the clinical application of Vitex/casticin for hematopoietic malignancy.

HOXA9 is critical in the proliferation, differentiation, and malignancy of leukaemia cells both in vitro and in vivo.

PubMed

Chen, Shibing; Yu, Juan; Lv, Xin; Zhang, Lijuan

2017-10-01

Progress in the understanding of the molecular mechanism for acute myeloid leukaemia is of great significance to generate new potential targets for treatment. Recent studies showed that HOXA9, a homeodomain-containing transcription factor, is commonly deregulated in acute leukaemia. In this study, we elucidated the direct correlation between HoxA9 expression and progression of leukaemia using 2 different types of leukaemia cells HL-60 and MOLT-3. The HoxA9 expression level was decreased in leukaemia cells with the treatment of all-trans retinoic acid or arsenic trioxide (As 2 O 3 ). Downregulation of HoxA9 could impair the proliferation and promote the leukaemia cell death. HoxA9 silencing also potentiated the differentiation of leukaemia cells, and in vivo studies demonstrated that HoxA9 downregulation could interfere the tumour growth. Interestingly, HoxA9 silencing also led to the alteration in miRNA expression, mediating the promoting effect on the leukaemia cell differentiation. Therefore, this work provided a promising and potentially efficient target to leukaemia treatment, indicating that HoxA9 is likely to be an ideal candidate in the gene therapy against acute myeloid leukaemia. In this study, we elucidated the critical role of HoxA9 in the proliferation and differentiation of leukaemia cells both in vitro and in vivo. The effect of HoxA9 modulation was correlated with the clinical effect of all-trans retinoic acid and As 2 O 3 . Furthermore, HoxA9 also regulated the miRNA expression, controlling the leukaemia cell differentiation. Therefore, this work provided new insights into molecular mechanism underlying the leukaemia treatment, potentially putting forward a brand new target to the gene therapy against leukaemia. Copyright © 2017 John Wiley & Sons, Ltd.

Dexamethasone enhances interaction of endogenous annexin 1 with L-selectin and triggers shedding of L-selectin in the monocytic cell line U-937.

PubMed

de Coupade, Catherine; Solito, Egle; Levine, Jon D

2003-09-01

(1) L-selectin, constitutively expressed by leukocytes, is involved in the initial binding of leukocytes to activated endothelium. Anti-inflammatory drugs like glucocorticoids can induce shedding of L-selectin, but the mechanism is still unknown. Annexin 1, a protein whose synthesis and externalization/secretion are induced during the inflammatory response, has been proposed as a mediator of the anti-inflammatory actions of glucocorticoids. (2) The monocytic cell line U-937 strongly expresses Annexin 1 after 24 h of phorbol 12-myristate 13-acetate (PMA, 1 nm) treatment and externalizes/releases the protein after additional 16 h of dexamethasone (1 microm) treatment. (3) This study investigated the possible regulation of cell surface L-selectin shedding by endogenous Annexin 1, and its role in glucocorticoid-induced L-selectin shedding in the U-937 cell line. (4) PMA- and dexamethasone treatment-induced L-selectin shedding was potentially mediated by Annexin 1, since neutralizing antibodies against Annexin 1 reduced dexamethasone- and Annexin 1-induced shedding. (5) Immunoprecipitation and binding assays provided support for the suggestion that this effect could be mediated by an interaction between externalized Annexin 1 and L-selectin. Such interaction involved the N-terminal domain of Annexin 1 and was calcium-dependent. Confocal microscopy studies demonstrated increased colocalization of Annexin 1 and L-selectin on the cell surface. (6) Overall, our study provides new insights into the potential role of endogenous ANXA1 as a mediator of dexamethasone-induced L-selectin shedding, which may contribute to the anti-inflammatory activity of glucocorticoids.

Nanosized aluminum altered immune function.

PubMed

Braydich-Stolle, Laura K; Speshock, Janice L; Castle, Alicia; Smith, Marcus; Murdock, Richard C; Hussain, Saber M

2010-07-27

On the basis of their uses in jet fuels and munitions, the most likely scenario for aluminum nanoparticle (NP) exposure is inhalation. NPs have been shown to be capable of penetrating deep into the alveolar regions of the lung, and therefore human alveolar macrophages (U937) with human type II pneumocytes (A549) were cultured together and exposed to NPs dispersed in an artificial lung surfactant to more accurately mimic the lung microenvironment. Two types of NPs were evaluated: aluminum (Al) and aluminum oxide (Al2O3). Following a 24-h incubation, cell viability was assessed using MTS, and mild toxicity was observed at higher doses with the U937 cells affected more than the A549. Since the U937 cells provided protection from NP toxicity, the cocultures were exposed to a benign concentration of NPs and infected with the respiratory pathogen community-associated methicillin-resistant Staphylococcus aureus (ca-MRSA) to determine any changes in cellular function. Phagocytosis assays demonstrated that the NPs impaired phagocytic function, and bacterial growth curves confirmed that this reduction in phagocytosis was not related to NP-bacteria interactions. Furthermore, NFkappaB PCR arrays and an IL-6 and TNF-alpha real time PCR demonstrated that both types of NPs altered immune response activation. This change was confirmed by ELISA assays that evaluated the secretion of IL-6, IL-8, IL-10, IL-1beta, and TNF-alpha and illustrated that the NPs repressed secretion of these cytokines. Therefore, although the NPs were not toxic to the cells, they did impair the cell's natural ability to respond to a respiratory pathogen regardless of NP composition.

U-937 Toxicity Testing of Lunar Dust Stimulant (JSC-1A-vf)

NASA Technical Reports Server (NTRS)

Bales, Kristyn; Hammond, Dianne; Wallace, William; Jeevarajan, Antony

2007-01-01

With NASA planning to extend the human presence to the moon by 2020, the dangers of the lunar environment must be assessed and appropriate countermeasures must be developed. Possible toxic effects of the lunar dust are of particular importance to human health because of the dust's chemical composition, reactivity, and small size. This project focuses on the toxicity of lunar dust stimulant (JSC-1A-vf), in both its active and passive forms, using U-937 human monocyte cells. Simulant was mechanically activated from its passive form by grinding, and its ability to produce hydroxyl radicals was determined. To test for toxicity, active and passivated simulant was diluted in media and applied to the cells for various time periods. Toxicity was then estimated using flow cytometry on the Guava Personal Cell Analysis system. Preliminary results suggest that passivated stimulant is slightly toxic, with an increase in toxicity for activated stimulant. Toxicity results may be affected by cell lysing behavior and quenching of hydroxyl radical production by the cell media.

Diterpenes from Xylopia langsdorffiana inhibit cell growth and induce differentiation in human leukemia cells.

PubMed

Castello Branco, Marianna V S; Anazetti, Maristella C; Silva, Marcelo S; Tavares, Josean F; Diniz, Margareth F F Melo; Frungillo, Lucas; Haun, Marcela; Melo, Patrícia S

2009-01-01

Two new diterpenes were isolated from stems and leaves of Xylopia langsdorffiana, ent-atisane-7alpha,16alpha-diol (xylodiol) and ent-7alpha-acetoxytrachyloban-18-oic acid (trachylobane), along with the known 8(17),12E,14-labdatrien-18-oic acid (labdane). We investigated their antitumour effects on HL60, U937 and K562 human leukemia cell lines. We found that xylodiol was the most potent diterpene in inhibiting cell proliferation of HL60, U937 and K562 cells, with mean IC50 values of 90, 80 and 50 microM, respectively. Based on the nitroblue tetrazolium (NBT) reduction assay, all the diterpenes were found to induce terminal differentiation in HL60 and K562 cells, with xylodiol being the most effective. NBT reduction was increased by almost 120% after 12 h exposure of HL60 cells to xylodiol at a concentration lower than the IC50 (50 microM). Thus, xylodiol inhibited human leukemia cell growth in vitro partly by inducing cell differentiation, and merits further studies to examine its mechanism of action as a potential antitumoural agent.

Evaluation of the Genetic Response of U937 and Jurkat Cells to 10-Nanosecond Electrical Pulses (nsEP)

PubMed Central

Glickman, Randolph D.; Tolstykh, Gleb P.; Estlack, Larry E.; Moen, Erick K.; Echchgadda, Ibtissam; Beier, Hope T.; Barnes, Ronald A.; Ibey, Bennett L.

2016-01-01

Nanosecond electrical pulse (nsEP) exposure activates signaling pathways, produces oxidative stress, stimulates hormone secretion, causes cell swelling and induces apoptotic and necrotic death. The underlying biophysical connection(s) between these diverse cellular reactions and nsEP has yet to be elucidated. Using global genetic analysis, we evaluated how two commonly studied cell types, U937 and Jurkat, respond to nsEP exposure. We hypothesized that by studying the genetic response of the cells following exposure, we would gain direct insight into the stresses experienced by the cell and in turn better understand the biophysical interaction taking place during the exposure. Using Ingenuity Systems software, we found genes associated with cell growth, movement and development to be significantly up-regulated in both cell types 4 h post exposure to nsEP. In agreement with our hypothesis, we also found that both cell lines exhibit significant biological changes consistent with mechanical stress induction. These results advance nsEP research by providing strong evidence that the interaction of nsEPs with cells involves mechanical stress. PMID:27135944

Molecular alterations in acute myeloid leukemia and their clinical and therapeutical implications.

PubMed

Infante, María Stefania; Piris, Miguel Ángel; Hernández-Rivas, José Ángel

2018-06-09

Acute myeloid leukaemia is the most common form of acute leukaemia, and its incidence increases with age. The disease derives from a transformed multipotent malignant haematopoietic stem cell that acquires consequent genomic alterations. The identification of recurrent cytogenetic anomalies associated with different patterns of acute myeloid leukaemia clinical presentation has led to the incorporation of genetic markers in clinical decision-making. In addition, the observation that these anomalies may mark therapeutic responses and relapse and survival rates have been incorporated into the World Health Organisation's recent molecular classification and stratification and the European Leukaemia Net, with the aim of creating prognostic categories that help rationalise better diagnosis, prognosis, re-evaluation of the disease and the combination of therapeutic protocols in order to increase the survival rate of these patients. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Li; Weng, Wei; Sun, Zhi-Xin

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, andmore » 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.« less

Development of an in vitro skin sensitization test using human cell lines; human Cell Line Activation Test (h-CLAT). II. An inter-laboratory study of the h-CLAT.

PubMed

Sakaguchi, H; Ashikaga, T; Miyazawa, M; Yoshida, Y; Ito, Y; Yoneyama, K; Hirota, M; Itagaki, H; Toyoda, H; Suzuki, H

2006-08-01

Recent regulatory changes have placed a major emphasis on in vitro safety testing and alternative models. In regard to skin sensitization tests, dendritic cells (DCs) derived from human peripheral blood have been considered in the development of new in vitro alternatives. Human cell lines have been also reported recently. In our previous study, we suggested that measuring CD86 and/or CD54 expression on THP-1 cells (human monocytic leukemia cell line) could be used as an in vitro skin sensitization method. An inter-laboratory study among two laboratories was undertaken in Japan in order to further develop an in vitro skin sensitization model. In the present study, we used two human cell lines: THP-1 and U-937 (human histiocytic lymphoma cell line). First we optimized our test protocol (refer to the related paper entitled "optimization of the h-CLAT protocol" within this journal) and then we did an inter-laboratory validation with nine chemicals using the optimized protocol. We measured the expression of CD86 and CD54 on the above cells using flow cytometry after a 24h and 48h exposure to six known allergens (e.g., DNCB, pPD, NiSO(4)) and three non-allergens (e.g., SLS, tween 80). For the sample test concentration, four doses (0.1x, 0.5x, 1x, and 2x of the 50% inhibitory concentration (IC(50))) were evaluated. IC(50) was calculated using MTT assay. We found that allergens/non-allergens were better predicted using THP-1 cells compared to U-937 cells following a 24 h and a 48 h exposure. We also found that the 24h treatment time tended to have a better accuracy than the 48 h treatment time for THP-1 cells. Expression of CD86 and CD54 were good predictive markers for THP-1 cells, but for U-937 cells, expression of CD86 was a better predictor than CD54, at the 24h and the 48 h treatment time. The accuracy also improved when both markers (CD86 and CD54) were used as compared with a single marker for THP-1 cells. Both laboratories gave a good prediction of allergen/non-allergen, especially using THP-1 cells. These results suggest that our method, human Cell Line Activation Test (h-CLAT), using human cell lines THP-1 and U-937, but especially THP-1 cells at 24h treatment, may be a useful in vitro skin sensitization model to predict various contact allergens.

Chronic effects of ethanol and/or darunavir/ritonavir on U937 monocytic cells: Regulation of cytochrome P450 and antioxidant enzymes, oxidative stress, and cytotoxicity

PubMed Central

Rao, P.S.S.; Kumar, Santosh

2015-01-01

Background Our recent study has shown that acute treatment with ethanol increases oxidative stress and cytotoxicity through cytochrome P450 2E1 (CYP2E1)-mediated pathway in U937 monocytic cells. U937 cells are derived from blood monocytes and are considered as the model system for HIV-related study. Since the prevalence of alcohol use in HIV-infected population is high, and HIV+ patients are on antiretroviral therapy (ART) soon after they are diagnosed, it is important to study the interactions between ethanol and ART in monocytes. Methods This study examined the chronic effects of ethanol and ART (darunavir/ritonavir), alone and in combination, on expression/levels of cytochrome P450 enzymes (CYPs), antioxidant enzymes (AOEs), reactive oxygen species (ROS), and cytotoxicity in U937 cells. The mRNA and protein levels were measured using quantitative RTPCR and Western blot, respectively. ROS and cytotoxicity were measured using flow cytometry and XTT assay, respectively. Results While chronic ART treatment increased CYP2E1 protein expression by 2-fold, ethanol and ethanol+ART increased CYP2E1 by ~5-fold. In contrast, ART and ethanol treatments decreased CYP3A4 protein expression by 38±17% and 74±15%, respectively, and the combination additively decreased CYP3A4 level by 90±8%. Expressions of superoxide dismutase (SOD1) and peroxiredoxin (PRDX6) were decreased by both ethanol and ART, however, the expressions of SOD2 and catalase were unaltered. These results suggested increased ethanol metabolism, increased ART accumulation, and decreased defense against ROS. Therefore, we determined the effects of ethanol and ART on ROS and cytotoxicity. While ART showed a slight increase, ethanol and ethanol+ART displayed significant increase in ROS and cytotoxicity. Moreover, the combination showed additive effects on ROS and cytotoxicity. Conclusions These results suggest that chronic ethanol, in the absence and presence of ART, increases ROS and cytotoxicity in monocytes, perhaps via CYPs and AOEs mediated pathways. This study has clinical implications in HIV+ alcohol users who are on ART. PMID:26727525

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

PubMed

Hodroj, Mohammad Hassan; Jardaly, Achraf; Abi Raad, Sarah; Zouein, Annalise; Rizk, Sandra

2018-01-01

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

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

PubMed Central

Hodroj, Mohammad Hassan; Jardaly, Achraf; Abi Raad, Sarah; Zouein, Annalise; Rizk, Sandra

2018-01-01

Background Topotecan (TP) is an anticancer drug acting as topoisomerase I inhibitor that is used in the treatment of many types of cancers including leukemia, but it has significant side effects. Andrographolide, a compound extracted from Andrographis paniculata, was recently proven to inhibit the growth of cancer cells and can induce apoptosis. The aim of this study is to investigate the possible synergism between TP and andrographolide in acute myeloid cells in vitro. Materials and methods U937 acute myeloid leukemic cells were cultured using Roswell Park Memorial Institute (RPMI) medium and then treated for 24 h with TP and andrographolide prepared through the dilution of dimethyl sulfoxide (DMSO) stocks with RPMI on the day of treatment. Cell proliferation was assessed using cell proliferation assay upon treatment with both compounds separately and in combination. Cell-cycle study and apoptosis detection were performed by staining the cells with propidium iodide (PI) stain and Annexin V/PI stain, respectively, followed by flow cytometry analysis. Western blotting was used to assess the expression of various proteins involved in apoptotic pathways. Results Both TP and andrographolide showed an antiproliferative effect in a dose-dependent manner when applied on U937 cells separately; however, pretreating the cells with andrographolide before applying TP exhibited a synergistic effect with lower inhibitory concentrations (half-maximal inhibitory concentration). Treating the cells with TP alone led to specific cell-cycle arrest at S phase that was more prominent upon pretreatment combination with andrographolide. Using Annexin V/PI staining to assess the proapoptotic effect following the pretreatment combination showed an increase in the number of apoptotic cells, which was supported by the Western blot results that manifested an upregulation of several proapoptotic proteins expression. Conclusion The pretreatment of U937 with andrographolide followed by low doses of TP showed an enhancement in inducing apoptosis when compared to the application of each compound separately. PMID:29785137

Droplet microfluidic technology for single-cell high-throughput screening.

PubMed

Brouzes, Eric; Medkova, Martina; Savenelli, Neal; Marran, Dave; Twardowski, Mariusz; Hutchison, J Brian; Rothberg, Jonathan M; Link, Darren R; Perrimon, Norbert; Samuels, Michael L

2009-08-25

We present a droplet-based microfluidic technology that enables high-throughput screening of single mammalian cells. This integrated platform allows for the encapsulation of single cells and reagents in independent aqueous microdroplets (1 pL to 10 nL volumes) dispersed in an immiscible carrier oil and enables the digital manipulation of these reactors at a very high-throughput. Here, we validate a full droplet screening workflow by conducting a droplet-based cytotoxicity screen. To perform this screen, we first developed a droplet viability assay that permits the quantitative scoring of cell viability and growth within intact droplets. Next, we demonstrated the high viability of encapsulated human monocytic U937 cells over a period of 4 days. Finally, we developed an optically-coded droplet library enabling the identification of the droplets composition during the assay read-out. Using the integrated droplet technology, we screened a drug library for its cytotoxic effect against U937 cells. Taken together our droplet microfluidic platform is modular, robust, uses no moving parts, and has a wide range of potential applications including high-throughput single-cell analyses, combinatorial screening, and facilitating small sample analyses.

Synergistic in-vitro effects of combining an antiglycolytic, 3-bromopyruvate, and a bromodomain-4 inhibitor on U937 myeloid leukemia cells.

PubMed

Kapp, Nicolette; Stander, Xiao X; Stander, Barend A

2018-06-01

This project investigated the in-vitro effects of a glycolytic inhibitor, 3-bromopyruvate (3-BrP), in combination with and a new in silico-designed inhibitor of the bromodomain-4 (BRD-4) protein, ITH-47, on the U937 acute myeloid leukemia cell line. 3-BrP is an agent that targets the altered metabolism of cancer cells by interfering with glucose metabolism in the glycolytic pathway. ITH-47 is an acetyl-lysine inhibitor that displaces bromdomain 4 proteins from chromatin by competitively binding to the acetyl-lysine recognition pocket of this bromodomain and extraterminal (BET) BRD protein, thereby preventing transcription of cancer-associated genes and further cell growth. Cell growth studies determined the IC50 after 48 h exposure for 3-BrP and ITH-47 to be 6 and 2 μmol/l, respectively. When combined, 2.4 and 1 μmol/l of 3-BrP and ITH-47, respectively, inhibited 50% of the cell population, yielding a synergistic combination index of 0.9. Subsequent mechanistic studies showed that the IC50 concentrations of ITH-47 and 3-BrP and the combination increased observable apoptotic bodies and cell shrinkage in U937 cells treated for 48 h. Cell cycle analysis showed an increase in the sub-G1 fraction in all treated cells, suggesting that cell death was increased in the treated samples. Annexin-V-FITC apoptosis analysis showed a statistically significant increase in the number of cells in early and late apoptosis, indicating that cell death occurred through apoptosis and not necrosis. Only U937 cells exposed to ITH-47 showed a decrease in mitochondrial membrane potential compared with the vehicle control. Reactive oxygen species production was decreased in all treated samples. ITH-47-exposed cells showed a decrease in c-Myc, Bcl-2, and p53 gene expressions. 3-BrP-treated cells showed an increase in c-myc and p53 gene expressions. The combination of ITH-47 and 3-BrP lead to downregulation of c-myc and Bcl-2 genes. ITH-47 exposure conditions yielded a marked decrease in c-myc protein levels as well as a decrease in Ser70 phosphorylated Bcl-2. Analysis of 3-BrP and the combination of ITH-47 and 3-BrP test conditions indicated an increase in p53 protein levels. This novel study is the first to investigate the in-vitro synergistic therapeutic effect of ITH-47 and 3-BrP. The current study contributes toward unraveling the in-vitro molecular mechanisms and signal transduction associated with a novel combination of BRD inhibitors and antiglycolytic agents, providing a basis for further research on these combinations.

Alginate foam-based three-dimensional culture to investigate drug sensitivity in primary leukaemia cells.

PubMed

Karimpoor, Mahroo; Yebra-Fernandez, Eva; Parhizkar, Maryam; Orlu, Mine; Craig, Duncan; Khorashad, Jamshid S; Edirisinghe, Mohan

2018-04-01

The development of assays for evaluating the sensitivity of leukaemia cells to anti-cancer agents is becoming an important aspect of personalized medicine. Conventional cell cultures lack the three-dimensional (3D) structure of the bone marrow (BM), the extracellular matrix and stromal components which are crucial for the growth and survival of leukaemia stem cells. To accurately predict the sensitivity of the leukaemia cells in an in vitro assay a culturing system containing the essential components of BM is required. In this study, we developed a porous calcium alginate foam-based scaffold to be used for 3D culture. The new 3D culture was shown to be cell compatible as it supported the proliferation of both normal haematopoietic and leukaemia cells. Our cell differential assay for myeloid markers showed that the porous foam-based 3D culture enhanced myeloid differentiation in both leukaemia and normal haematopoietic cells compared to two-dimensional culture. The foam-based scaffold reduced the sensitivity of the leukaemia cells to the tested antileukaemia agents in K562 and HL60 leukaemia cell line model and also primary myeloid leukaemia cells. This observation supports the application of calcium alginate foams as scaffold components of the 3D cultures for investigation of sensitivity to antileukaemia agents in primary myeloid cells. © 2018 The Author(s).

Enhanced cell killing and apoptosis of oral squamous cell carcinoma cells with ultrasound in combination with cetuximab coated albumin microbubbles.

PubMed

Narihira, Kyoichi; Watanabe, Akiko; Sheng, Hong; Endo, Hitomi; Feril, Loreto B; Irie, Yutaka; Ogawa, Koichi; Moosavi-Nejad, Seyedeh; Kondo, Seiji; Kikuta, Toshihiro; Tachibana, Katsuro

2018-03-01

Targeted microbubbles have the potential to be used for ultrasound (US) therapy and diagnosis of various cancers. In the present study, US was irradiated to oral squamous cell carcinoma cells (HSC-2) in the presence of cetuximab-coated albumin microbubbles (CCAM). Cell killing rate with US treatment at 0.9 W/cm 2 and 1.0 W/cm 2 in the presence of CCAM was greater compared to non-targeted albumin microbubbles (p < .05). On the other hand, selective cell killing was not observed in human myelomonocytic lymphoma cell line (U937) that had no affinity to cetuximab. Furthermore, US irradiation in the presence of CCAM showed a fivefold increase of cell apoptotic rate for HSC-2 cells (21.0 ± 3.8%) as compared to U937 cells (4.0 ± 0.8%). Time-signal intensity curve in a tissue phantom demonstrated clear visualisation of CCAM with conventional US imaging device. Our experiment verifies the hypothesis that CCAM was selective to HSC-2 cells and may be applied as a novel therapeutic/diagnostic microbubble for oral squamous cell carcinoma.

New Approach in Translational Medicine: Effects of Electrolyzed Reduced Water (ERW) on NF-κB/iNOS Pathway in U937 Cell Line under Altered Redox State

PubMed Central

Franceschelli, Sara; Gatta, Daniela Maria Pia; Pesce, Mirko; Ferrone, Alessio; Patruno, Antonia; de Lutiis, Maria Anna; Grilli, Alfredo; Felaco, Mario; Croce, Fausto; Speranza, Lorenza

2016-01-01

It is known that increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) can exert harmful effects, altering the cellular redox state. Electrolyzed Reduced Water (ERW) produced near the cathode during water electrolysis exhibits high pH, high concentration of dissolved hydrogen and an extremely negative redox potential. Several findings indicate that ERW had the ability of a scavenger free radical, which results from hydrogen molecules with a high reducing ability and may participate in the redox regulation of cellular function. We investigated the effect of ERW on H2O2-induced U937 damage by evaluating the modulation of redox cellular state. Western blotting and spectrophotometrical analysis showed that ERW inhibited oxidative stress by restoring the antioxidant capacity of superoxide dismutase, catalase and glutathione peroxidase. Consequently, ERW restores the ability of the glutathione reductase to supply the cell of an important endogenous antioxidant, such as GSH, reversing the inhibitory effect of H2O2 on redox balance of U937 cells. Therefore, this means a reduction of cytotoxicity induced by peroxynitrite via a downregulation of the NF-κB/iNOS pathway and could be used as an antioxidant for preventive and therapeutic application. In conclusion, ERW can protect the cellular redox balance, reducing the risk of several diseases with altered cellular homeostasis such as inflammation. PMID:27598129

Unidirectional Flux Balance of Monovalent Ions in Cells with Na/Na and Li/Na Exchange: Experimental and Computational Studies on Lymphoid U937 Cells

PubMed Central

Vereninov, Igor A.; Yurinskaya, Valentina E.; Model, Michael A.; Vereninov, Alexey A.

2016-01-01

Monovalent ion traffic across the cell membrane occurs via various pathways. Evaluation of individual fluxes in whole cell is hampered by their strong interdependence. This difficulty can be overcome by computational analysis of the whole cell flux balance. However, the previous computational studies disregarded ion movement of the self-exchange type. We have taken this exchange into account. The developed software allows determination of unidirectional fluxes of all monovalent ions via the major pathways both under the balanced state and during transient processes. We show how the problem of finding the rate coefficients can be solved by measurement of monovalent ion concentrations and some of the fluxes. Interdependence of fluxes due to the mandatory conditions of electroneutrality and osmotic balance and due to specific effects can be discriminated, enabling one to identify specific changes in ion transfer machinery under varied conditions. To test the effectiveness of the developed approach we made use of the fact that Li/Na exchange is known to be an analogue of the coupled Na/Na exchange. Thus, we compared the predicted and experimental data obtained on U937 cells under varied Li+ concentrations and following inhibition of the sodium pump with ouabain. We found that the coupled Na/Na exchange in U937 cells comprises a significant portion of the entire Na+ turnover. The data showed that the loading of the sodium pump by Li/Na exchange involved in the secondary active Li+ transport at 1–10 mM external Li+ is small. This result may be extrapolated to similar Li+ and Na+ flux relationships in erythrocytes and other cells in patients treated with Li+ in therapeutic doses. The developed computational approach is applicable for studying various cells and can be useful in education for demonstrating the effects of individual transporters and channels on ion gradients, cell water content and membrane potential. PMID:27159324

Apoptosis is rapidly triggered by antisense depletion of MCL-1 in differentiating U937 cells.

PubMed

Moulding, D A; Giles, R V; Spiller, D G; White, M R; Tidd, D M; Edwards, S W

2000-09-01

Mcl-1 is a member of the Bcl-2 protein family, which has been shown to delay apoptosis in transfection and/or overexpression experiments. As yet no gene knockout mice have been engineered, and so there is little evidence to show that loss of Mcl-1 expression is sufficient to trigger apoptosis. U937 cells constitutively express the antiapoptotic protein Bcl-2; but during differentiation, in response to the phorbol ester PMA (phorbol 12 beta-myristate 13 alpha-acetate), Mcl-1 is transiently induced. The purpose of this investigation was to determine the functional role played by Mcl-1 in this differentiation program. Mcl-1 expression was specifically disrupted by chimeric methylphosphonate/phosphodiester antisense oligodeoxynucleotides to just 5% of control levels. The depletion of Mcl-1 messenger RNA (mRNA) and protein was both rapid and specific, as indicated by the use of control oligodeoxynucleotides and analysis of the expression of other BCL2 family members and PMA-induced tumor necrosis factor-alpha (TNF-alpha). Specific depletion of Mcl-1 mRNA and protein, in the absence of changes in cellular levels of Bcl-2, results in a rapid entry into apoptosis. Levels of the proapoptotic protein Bax remained unchanged during differentiation, while Bak expression doubled within 24 hours. Apoptosis was detected within 4 hours of Mcl-1 antisense treatment by a variety of parameters including a novel live cell imaging technique allowing correlation of antisense treatment and apoptosis in individual cells. The induction of Mcl-1 is required to prevent apoptosis during differentiation of U937 cells, and the constitutive expression of Bcl-2 is unable to compensate for the loss of Mcl-1. (Blood. 2000;96:1756-1763)

Mycobacterium tuberculosis surface protein Rv0227c contains high activity binding peptides which inhibit cell invasion.

PubMed

Rodríguez, Diana Marcela; Ocampo, Marisol; Curtidor, Hernando; Vanegas, Magnolia; Patarroyo, Manuel Elkin; Patarroyo, Manuel Alfonso

2012-12-01

Mycobacterium tuberculosis surface proteins involved in target cell invasion may be identified as a strategy for developing subunit-based, chemically-synthesized vaccines. The Rv0227c protein was thus selected to assess its role in the invasion and infection of Mycobacterium tuberculosis target cells. Results revealed Rv0227c localization on mycobacterial surface by immunoelectron microscopy and Western blot. Receptor-ligand assays using 20-mer, non-overlapping peptides covering the complete Rv0227c protein sequence revealed three high activity binding peptides for U937 phagocytic cells and seven for A549 cells. Peptide 16944 significantly inhibited mycobacterial entry to both cell lines while 16943 and 16949 only managed to inhibit entrance to U937 cells and 16951 to A549 cells. The Jnet bioinformatics tool predicted secondary structure elements for the complete protein, agreeing with elements determined for such chemically-synthesized peptides. It was thus concluded that high activity binding peptides which were able to inhibit mycobacterial entry to target cells are of great importance when selecting peptide candidates for inclusion in an anti-tuberculosis vaccine. Copyright © 2012 Elsevier Inc. All rights reserved.

Acute B lymphoblastic leukaemia-propagating cells are present at high frequency in diverse lymphoblast populations

PubMed Central

Rehe, Klaus; Wilson, Kerrie; Bomken, Simon; Williamson, Daniel; Irving, Julie; den Boer, Monique L; Stanulla, Martin; Schrappe, Martin; Hall, Andrew G; Heidenreich, Olaf; Vormoor, Josef

2013-01-01

Leukaemia-propagating cells are more frequent in high-risk acute B lymphoblastic leukaemia than in many malignancies that follow a hierarchical cancer stem cell model. It is unclear whether this characteristic can be more universally applied to patients from non-‘high-risk’ sub-groups and across a broad range of cellular immunophenotypes. Here, we demonstrate in a wide range of primary patient samples and patient samples previously passaged through mice that leukaemia-propagating cells are found in all populations defined by high or low expression of the lymphoid differentiation markers CD10, CD20 or CD34. The frequency of leukaemia-propagating cells and their engraftment kinetics do not differ between these populations. Transcriptomic analysis of CD34high and CD34low blasts establishes their difference and their similarity to comparable normal progenitors at different stages of B-cell development. However, consistent with the functional similarity of these populations, expression signatures characteristic of leukaemia propagating cells in acute myeloid leukaemia fail to distinguish between the different populations. Together, these findings suggest that there is no stem cell hierarchy in acute B lymphoblastic leukaemia. PMID:23229821

The role of hypoxia inducible factor-1α in the increased MMP-2 and MMP-9 production by human monocytes exposed to nickel nanoparticles.

PubMed

Wan, Rong; Mo, Yiqun; Chien, Sufan; Li, Yihua; Li, Yixin; Tollerud, David J; Zhang, Qunwei

2011-12-01

Nickel is an important economic commodity, but it can cause skin sensitization and may cause lung diseases such as lung fibrosis, pneumonitis, bronchial asthma and lung cancer. With development of nanotechnology, nano-sized nickel (Nano-Ni) and nano-sized titanium dioxide (Nano-TiO₂) particles have been developed and produced for many years with new formulations and surface properties to meet novel demands. Our previous studies have shown that Nano-Ni instilled into rat lungs caused a greater inflammatory response as compared with standard-sized nickel (5 μm) at equivalent mass concentrations. Nano-Ni caused a persistent high level of inflammation in lungs even at low doses. Recently, several studies have shown that nanoparticles can translocate from the lungs to the circulatory system. To evaluate the potential systemic effects of metal nanoparticles, we compared the effects of Nano-Ni and Nano-TiO₂ on matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) gene expression and activity. Our results showed that exposure of human monocyte U937 to Nano-Ni caused dose- and time- dependent increase in MMP-2 and MMP-9 mRNA expression and pro-MMP-2 and pro-MMP-9 activity, but Nano-TiO₂ did not. Nano-Ni also caused dose- and time- related increase in tissue inhibitor of metalloproteinases 1 (TIMP-1), but Nano-TiO₂ did not. To determine the potential mechanisms involved, we measured the expression of hypoxia inducible factor 1α (HIF-1α) in U937 cells exposed to Nano-Ni and Nano-TiO₂. Our results showed that exposure to Nano-Ni caused HIF-1α accumulation in the nucleus. Furthermore, pre-treatment of U937 cells with heat shock protein 90 (Hsp90) inhibitor, 17-(Allylamino)-17-demethoxygeldanamycin (17-AAG), prior to exposure to Nano-Ni significantly abolished Nano-Ni-induced MMP-2 and MMP-9 mRNA upregulation and increased pro-MMP-2 and pro-MMP-9 activity. Our results suggest that HIF-1α accumulation may be involved in the increased MMP-2 and MMP-9 production in U937 cells exposed to Nano-Ni.

Five novel naphthylisoquinoline alkaloids with growth inhibitory activities against human leukemia cells HL-60, K562 and U937 from stems and leaves of Ancistrocladus tectorius.

PubMed

Jiang, Chao; Li, Zhan-Lin; Gong, Ping; Kang, Sheng-Li; Liu, Ming-Sheng; Pei, Yue-Hu; Jing, Yong-Kui; Hua, Hui-Ming

2013-12-01

Two new 7,6'-coupled naphthylisoquinolines, namely ancistrotectorines A (1) and B (2), two new 5,3'-coupled naphthylisoquinolines, namely ancistrotectorines C (3) and D (4), and one new 7,8-coupled naphthylisoquinoline, namely ancistrotectorine E (5), together with 9 known naphthylisoquinoline alkaloids, hamatine (6), ancistrobertsonine B (7), ancistrocladinine (8), hamatinine (9), ancistrotanzanine A (10), ancistrotanzanine B (11), ancistrotectoriline B (12), 7-epi-ancistrobrevine D (13), and ancistrotectorine (14), were isolated from the 70% EtOH extract of Ancistrocladus tectorius. Their structures were elucidated based on the extensive analysis of spectroscopic data (1D, 2D NMR and MS). Compound 5 exhibited inhibitory activities against HL-60, K562 and U937 cell lines with IC50 values of 1.70, 4.18 and 2.56 μM respectively. © 2013.

Oligosaccharide receptor mimics inhibit Legionella pneumophila attachment to human respiratory epithelial cells.

PubMed

Thomas, Richard J; Brooks, Tim J

2004-02-01

Legionnaire's disease is caused by the intracellular pathogen Legionella pneumophila, presenting as an acute pneumonia. Attachment is the key step during infection, often relying on an interaction between host cell oligosaccharides and bacterial adhesins. Inhibition of this interaction by receptor mimics offers possible novel therapeutic treatments. L. pneumophila attachment to the A549 cell line was significantly reduced by treatment with tunicamycin (73.6%) and sodium metaperiodate (63.7%). This indicates the importance of cell surface oligosaccharide chains in adhesion. A number of putative anti-adhesion compounds inhibited attachment to the A549 and U937 cell lines. The most inhibitory compounds were polymeric saccharides, GalNAcbeta1-4Gal, Galbeta1-4GlcNAc and para-nitrophenol. These compounds inhibited adhesion to a range of human respiratory cell lines, including nasal epithelial, bronchial epithelial and alveolar epithelial cell lines and the human monocytic cell line, U937. Some eukaryotic receptors for L. pneumophila were determined to be the glycolipids, asialo-GM1 and asialo-GM2 that contain the inhibitory saccharide moiety, GalNAcbeta1-4Gal. The identified compounds have the potential to be used as novel treatments for Legionnaire's disease.

Comparison of Virulence of Legionella longbeachae Strains in Guinea Pigs and U937 Macrophage-Like Cells

PubMed Central

Doyle, Robyn M.; Cianciotto, Nicholas P.; Banvi, Shaila; Manning, Paul A.; Heuzenroeder, Michael W.

2001-01-01

A guinea pig model of experimental legionellosis was established for assessment of virulence of isolates of Legionella longbeachae. The results showed that there were distinct virulence groupings of L. longbeachae serogroup 1 strains based on the severity of disease produced in this model. Statistical analysis of the animal model data suggests that Australian isolates of L. longbeachae may be inherently more virulent than non-Australian strains. Infection studies performed with U937 cells were consistent with the animal model studies and showed that isolates of this species were capable of multiplying within these phagocytic cells. Electron microscopy studies of infected lung tissue were also undertaken to determine the intracellular nature of L. longbeachae serogroup 1 infection. The data showed that phagosomes containing virulent L. longbeachae serogroup 1 appeared bloated, contained cellular debris and had an apparent rim of ribosomes while those containing avirulent L. longbeachae serogroup 1 were compact, clear and smooth. PMID:11500403

Acute myeloid/T-lymphoblastic leukaemia (AMTL): a distinct category of acute leukaemias with common pathogenesis in need of improved therapy.

PubMed

Gutierrez, Alejandro; Kentsis, Alex

2018-03-01

Advances in the classification of acute leukaemias have led to improved outcomes for a substantial fraction of patients. However, chemotherapy resistance remains a major problem for specific subsets of acute leukaemias. Here, we propose that a molecularly distinct subtype of acute leukaemia with shared myeloid and T cell lymphoblastic features, which we term acute myeloid/T-lymphoblastic leukaemia (AMTL), is divided across 3 diagnostic categories owing to variable expression of markers deemed to be defining of myeloid and T-lymphoid lineages, such as myeloperoxidase and CD3. This proposed diagnostic group is supported by (i) retained myeloid differentiation potential during early T cell lymphoid development, (ii) recognition that some cases of acute myeloid leukaemia (AML) harbour hallmarks of T cell development, such as T-cell receptor gene rearrangements and (iii) common gene mutations in subsets of AML and T cell acute lymphoblastic leukaemia (T-ALL), including WT1, PHF6, RUNX1 and BCL11B. This proposed diagnostic entity overlaps with early T cell precursor (ETP) T-ALL and T cell/myeloid mixed phenotype acute leukaemias (MPALs), and also includes a subset of leukaemias currently classified as AML with features of T-lymphoblastic development. The proposed classification of AMTL as a distinct entity would enable more precise prospective diagnosis and permit the development of improved therapies for patients whose treatment is inadequate with current approaches. © 2018 John Wiley & Sons Ltd.

Promyelocytic leukaemia zinc finger maintains self-renewal of male germline stem cells (mGSCs) and its expression pattern in dairy goat testis.

PubMed

Song, W; Zhu, H; Li, M; Li, N; Wu, J; Mu, H; Yao, X; Han, W; Liu, W; Hua, J

2013-08-01

Previous studies have shown that promyelocytic leukaemia zinc finger (PLZF) is a spermatogonia-specific transcription factor in the testis, required to regulate self-renewal and maintenance of the spermatogonia stem cell. Up to now, expression and function of PLZF in the goat testis has not been known. The objectives of this study were to investigate PLZF expression pattern in the dairy goat and its effect on male goat germline stem cell (mGSC) self-renewal and differentiation. Testis development and expression patterns of PLZF in the dairy goat were analysed by haematoxylin and eosin staining, immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). Furthermore, effects of PLZF overexpression on mGSC self-renewal and differentiation were evaluated by quantitative RT-PCR (QRT-PCR), immunofluorescence and BrdU incorporation assay. Promyelocytic leukaemia zinc finger was essential for dairy goat testis development and expression of several proliferation and pluripotency-associated proteins including OCT4, C-MYC were upregulated by PLZF overexpression. The study demonstrated that PLZF played a key role in maintaining self-renewal of mGSCs and its overexpression enhanced expression of proliferation-associated genes. Promyelocytic leukaemia zinc finger could function in the dairy goat as well as in other species in maintaining self-renewal of germline stem cells and this study provides a model to study the mechanism on self-renewal and differentiation of mGSCs in livestock. © 2013 John Wiley & Sons Ltd.

In Vitro Effects of Bromoalkyl Phenytoin Derivatives on Regulated Death, Cell Cycle and Ultrastructure of Leukemia Cells.

PubMed

Śladowska, Katarzyna; Opydo-Chanek, Małgorzata; Król, Teodora; Trybus, Wojciech; Trybus, Ewa; Kopacz-Bednarska, Anna; Handzlik, Jadwiga; Kieć-Kononowicz, Katarzyna; Mazur, Lidia

2017-11-01

To search for new antileukemic agents, the chemical structure of phenytoin was modified. A possible cytotoxic activity of three bromoalkyl phenytoin analogs, methyl 2-(1-(3-bromopropyl)-2,4-dioxo-5,5-diphenylimidazolidin-3-yl) propanoate (PH2), 1-(3-bromopropyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (PH3) and 1-(4-bromobutyl)-3-methyl-5,5-diphenylimidazolidine-2,4-dione (PH4) on regulated cell death, the cell cycle and cell ultrastructure was assessed. The experiments were performed in vitro on HL-60 and U937 cells, using flow cytometry and electron microscopy methods. Application of PH2, PH3, and PH4 resulted in cell surface exposure of phosphatidylserine and plasma membrane impairment, caspase-8, -9, and -3/7 activation, dissipation of mitochondrial membrane potential, DNA breakage, cell-cycle disturbance and cell ultrastructural changes. In general, PH3 appeared to be the most active against the leukemia cells, and all bromoalkyl hydantoins, PH2-PH4, were more active in HL-60 cells than in U937 cells. The antileukemic activity of the bromoalkyl phenytoin analogs depended on the combination of N-hydantoin substituents and the human cell line used. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

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

PubMed

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.

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

PubMed Central

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

2017-01-01

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. PMID:29152058

A comparative study of U937 cell size changes during apoptosis initiation by flow cytometry, light scattering, water assay and electronic sizing.

PubMed

Yurinskaya, Valentina; Aksenov, Nikolay; Moshkov, Alexey; Model, Michael; Goryachaya, Tatyana; Vereninov, Alexey

2017-10-01

A decrease in flow cytometric forward light scatter (FSC) is commonly interpreted as a sign of apoptotic cell volume decrease (AVD). However, the intensity of light scattering depends not only on the cell size but also on its other characteristics, such as hydration, which may affect the scattering in the opposite way. That makes estimation of AVD by FSC problematic. Here, we aimed to clarify the relationship between light scattering, cell hydration (assayed by buoyant density) and cell size by the Coulter technique. We used human lymphoid cells U937 exposed to staurosporine, etoposide or hypertonic stress as an apoptotic model. An initial increase in FSC was found to occur in apoptotic cells treated with staurosporine and hypertonic solutions; it is accompanied by cell dehydration and is absent in apoptosis caused by etoposide that is consistent with the lack of dehydration in this case. Thus, the effect of dehydration on the scattering signal outweighs the effect of reduction in cell size. The subsequent FSC decrease, which occurred in parallel to accumulation of annexin-positive cells, was similar in apoptosis caused by all three types of inducers. We conclude that an increase, but not a decrease in light scattering, indicates the initial cell volume decrease associated with apoptotic cell dehydration.

Cutting Edge: Inflammasome Activation in Primary Human Macrophages Is Dependent on Flagellin

PubMed Central

Kortmann, Jens; Brubaker, Sky W.

2015-01-01

Murine NLR family, apoptosis inhibitory protein (Naip)1, Naip2, and Naip5/6 are host sensors that detect the cytosolic presence of needle and rod proteins from bacterial type III secretion systems and flagellin, respectively. Previous studies using human-derived macrophage-like cell lines indicate that human macrophages sense the cytosolic needle protein, but not bacterial flagellin. In this study, we show that primary human macrophages readily sense cytosolic flagellin. Infection of primary human macrophages with Salmonella elicits robust cell death and IL-1β secretion that is dependent on flagellin. We show that flagellin detection requires a full-length isoform of human Naip. This full-length Naip isoform is robustly expressed in primary macrophages from healthy human donors, but it is drastically reduced in monocytic tumor cells, THP-1, and U937, rendering them insensitive to cytosolic flagellin. However, ectopic expression of full-length Naip rescues the ability of U937 cells to sense flagellin. In conclusion, human Naip functions to activate the inflammasome in response to flagellin, similar to murine Naip5/6. PMID:26109648

Gold nanoparticles synthesis and biological activity estimation in vitro and in vivo.

PubMed

Rieznichenko, L S; Dybkova, S M; Gruzina, T G; Ulberg, Z R; Todor, I N; Lukyanova, N Yu; Shpyleva, S I; Chekhun, V F

2012-01-01

The aim of the work was the synthesis of gold nanoparticles (GNP) of different sizes and the estimation of their biological activity in vitro and in vivo. Water dispersions of gold nanoparticles of different sizes have been synthesized by Davis method and characterized by laser-correlation spectroscopy and transmission electron microscopy methods. The GNP interaction with tumor cells has been visualized by confocal microscopy method. The enzyme activity was determined by standard biochemical methods. GNP distribution and content in organs and tissues have been determined via atomic-absorption spectrometry method; genotoxic influence has been estimated by "Comet-assay" method. The GNP size-dependent accumulation in cultured U937 tumor cells and their ability to modulate U937 cell membrane Na(+),K(+)-АТР-ase activity value has been revealed in vitro. Using in vivo model of Guerin carcinoma it has been shown that GNP possess high affinity to tumor cells. Our results indicate the perspectives of use of the synthesized GNP water dispersions for cancer diagnostics and treatment. It's necessary to take into account a size-dependent biosafety level of nanoparticles.

Membrane Transfer from Mononuclear Cells to Polymorphonuclear Neutrophils Transduces Cell Survival and Activation Signals in the Recipient Cells via Anti-Extrinsic Apoptotic and MAP Kinase Signaling Pathways.

PubMed

Li, Ko-Jen; Wu, Cheng-Han; Shen, Chieh-Yu; Kuo, Yu-Min; Yu, Chia-Li; Hsieh, Song-Chou

2016-01-01

The biological significance of membrane transfer (trogocytosis) between polymorphonuclear neutrophils (PMNs) and mononuclear cells (MNCs) remains unclear. We investigated the biological/immunological effects and molecular basis of trogocytosis among various immune cells in healthy individuals and patients with active systemic lupus erythematosus (SLE). By flow cytometry, we determined that molecules in the immunological synapse, including HLA class-I and-II, CD11b and LFA-1, along with CXCR1, are exchanged among autologous PMNs, CD4+ T cells, and U937 cells (monocytes) after cell-cell contact. Small interfering RNA knockdown of the integrin adhesion molecule CD11a in U937 unexpectedly enhanced the level of total membrane transfer from U937 to PMN cells. Functionally, phagocytosis and IL-8 production by PMNs were enhanced after co-culture with T cells. Total membrane transfer from CD4+ T to PMNs delayed PMN apoptosis by suppressing the extrinsic apoptotic molecules, BAX, MYC and caspase 8. This enhancement of activities of PMNs by T cells was found to be mediated via p38- and P44/42-Akt-MAP kinase pathways and inhibited by the actin-polymerization inhibitor, latrunculin B, the clathrin inhibitor, Pitstop-2, and human immunoglobulin G, but not by the caveolin inhibitor, methyl-β-cyclodextrin. In addition, membrane transfer from PMNs enhanced IL-2 production by recipient anti-CD3/anti-CD28 activated MNCs, and this was suppressed by inhibitors of mitogen-activated protein kinase (PD98059) and protein kinase C (Rottlerin). Of clinical significance, decreased total membrane transfer from PMNs to MNCs in patients with active SLE suppressed mononuclear IL-2 production. In conclusion, membrane transfer from MNCs to PMNs, mainly at the immunological synapse, transduces survival and activation signals to enhance PMN functions and is dependent on actin polymerization, clathrin activation, and Fcγ receptors, while membrane transfer from PMNs to MNCs depends on MAP kinase and PKC signaling. Defective membrane transfer from PMNs to MNCs in patients with active systemic lupus erythematous suppressed activated mononuclear IL-2 production.

Klinefelter syndrome and acute basophilic leukaemia--case report.

PubMed

Ljubić, Nives; Lang, Nada; Skelin, Ika Kardum; Lasan, Ruzica; Dominis, Mara; Perković, Leila; Zupanić-Krmek, Dubraka; Grgurević-Batinica, Anita

2010-06-01

Patients with 47, XXY karyotype (Klinefelter syndrome) appear to have increased risk of developing cancer, especially male breast cancer, germ cell tumours and non Hodgkin lymphomas, but rarely acute myeloid leukaemia. We report a patient with acute basophilic leukaemia with 47, XXY karyotype in both the tumour and constitutional cells. Acute basophilic leukaemia is very rare disease comprising less than 1% of all acute myeloid leukaemias. Morphological characteristic of leukaemic blast cells is moderately basophilic cytoplasm containing a variable number of coarse basophilic granules. The most characteristic cytochemical reaction is metachromatic positivity with toluidine blue. Blast are myeloperoxidase negative. Also leukemic blasts express myeloid and monocyte markers. There is no consistent chromosomal abnormality identified in this leukaemia. This is the first reported case of acute basophilic leukaemia in patient with Klinefelter syndrome. In this article the medical history of the patient is given and the possible connection between Klinefelter syndrome and acute myeloid leukaemia is discussed.

Blastic natural killer cell leukaemia in a dog--a case report.

PubMed

Bonkobara, Makoto; Saito, Taro; Yamashita, Masahiro; Tamura, Kyoichi; Yagihara, Hiroko; Isotani, Mayu; Sato, Takashi; Washizu, Tsukimi

2007-11-01

A case of canine non-T, non-B lymphoid leukaemia was determined to be of natural killer (NK) cell lineage by detecting specific expression of canine CD56 mRNA by reverse transcriptase polymerase chain reaction analysis. Although NK cells are usually considered to be morphologically large granular lymphocytes, the malignant NK cells in this case were agranular and blast-like, resembling human blastic NK cell leukaemia. The prognosis of human NK cell leukaemia is usually poor. In this case, the dog died 10 days after initial presentation, despite chemotherapy.

Tracing the origins of relapse in acute myeloid leukaemia to stem cells.

PubMed

Shlush, Liran I; Mitchell, Amanda; Heisler, Lawrence; Abelson, Sagi; Ng, Stanley W K; Trotman-Grant, Aaron; Medeiros, Jessie J F; Rao-Bhatia, Abilasha; Jaciw-Zurakowsky, Ivana; Marke, Rene; McLeod, Jessica L; Doedens, Monica; Bader, Gary; Voisin, Veronique; Xu, ChangJiang; McPherson, John D; Hudson, Thomas J; Wang, Jean C Y; Minden, Mark D; Dick, John E

2017-07-06

In acute myeloid leukaemia, long-term survival is poor as most patients relapse despite achieving remission. Historically, the failure of therapy has been thought to be due to mutations that produce drug resistance, possibly arising as a consequence of the mutagenic properties of chemotherapy drugs. However, other lines of evidence have pointed to the pre-existence of drug-resistant cells. For example, deep sequencing of paired diagnosis and relapse acute myeloid leukaemia samples has provided direct evidence that relapse in some cases is generated from minor genetic subclones present at diagnosis that survive chemotherapy, suggesting that resistant cells are generated by evolutionary processes before treatment and are selected by therapy. Nevertheless, the mechanisms of therapy failure and capacity for leukaemic regeneration remain obscure, as sequence analysis alone does not provide insight into the cell types that are fated to drive relapse. Although leukaemia stem cells have been linked to relapse owing to their dormancy and self-renewal properties, and leukaemia stem cell gene expression signatures are highly predictive of therapy failure, experimental studies have been primarily correlative and a role for leukaemia stem cells in acute myeloid leukaemia relapse has not been directly proved. Here, through combined genetic and functional analysis of purified subpopulations and xenografts from paired diagnosis/relapse samples, we identify therapy-resistant cells already present at diagnosis and two major patterns of relapse. In some cases, relapse originated from rare leukaemia stem cells with a haematopoietic stem/progenitor cell phenotype, while in other instances relapse developed from larger subclones of immunophenotypically committed leukaemia cells that retained strong stemness transcriptional signatures. The identification of distinct patterns of relapse should lead to improved methods for disease management and monitoring in acute myeloid leukaemia. Moreover, the shared functional and transcriptional stemness properties that underlie both cellular origins of relapse emphasize the importance of developing new therapeutic approaches that target stemness to prevent relapse.

Attenuation of cadmium-induced necrotic cell death by necrostatin-1: Potential necrostatin-1 acting sites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, T.-S.; Yang, P.-M.; Tsai, J.-S.

2009-03-01

Cadmium (Cd) induces necrotic death in Chinese hamster ovary (CHO) K1 cells and we have established the responsible signaling pathway. Reportedly, necrostatin-1 (Nec-1) rescues cells from necrotic death by mediating through the death domain receptor (DR) signaling pathway. We show here that Nec-1 also effectively attenuates necrotic death triggered by Cd. Two other treatments that cause necrotic cell death, one can (z-VAD-fmk/TNF-{alpha} on U937 cells) and the other cannot (etherynic acid (EA) on DLD-1 cells) be rescued by Nec-1, were also studied in parallel for comparison. Results show that Nec-1 is ineffectual in modulating intracellular calcium contents, calpain activity (amore » downstream protease), or reactive oxygen species production. It can counteract the reduction in mitochondrial membrane potential (MMP) caused by treating CHO K1 or U937 cells with necrosis-inducing agent. However, this effect was not found in EA-treated DLD-1 cells. Notably, Nec-1 elevates NF-{kappa}B activity in the presence or absence of necrosis-inducing agents. Our study shows that, in addition to DR-mediated necrosis, Nec-1 is effective in attenuating Cd-induced necrosis. It rescues cells with reduced MMP implying that mitochondrion is its major acting site.« less

[Immunophenotype of lymphoblastic leukaemia in children in relation to clinical symptoms and laboratory tests, preceding its diagnosis].

PubMed

Zapolska, Beata; Krawczuk-Rybak, Maryna; Łuczyński, Włodzimierz; Zak, Janusz; Leszczyńska, Elzbieta

2004-01-01

The aim of study was to compare the clinical picture and results of laboratory tests according to the acute lymphoblastic leukaemia (ALL) immunophenotype. The observation was carried out on a group of 67 patients treated in the IIIrd Department of Paediatrics and Department of Children Oncology in the Medical Academy of Białystok from January 1994 to April 2001. This group consists of 4 children with pro-B acute lymphoblastic leukaemia, 52 children with pre-B cell ALL, 1 child with B-cell acute lymphoblastic leukaemia and 9 children with T-cell acute lymphoblastic leukaemia. Haemorrhagic diathesis. splenomegaly, enlargement of peripheral lymph nodes as well as higher values of white blood cells count, blasts count, haemoglobin concentration, haematocrit and LDH activity were observed more frequently in patients with T-cell leukaemia than in others.

Hyaluronan inhibits prostaglandin E2 production via CD44 in U937 human macrophages.

PubMed

Yasuda, Tadashi

2010-03-01

Prostaglandin E(2) (PGE(2)) is one of the key mediators of inflammation in affected joints of rheumatoid arthritis (RA). Intra-articular injection of high molecular weight hyaluronan (HA) into RA knee joints relieves arthritic pain. Although HA has been shown to inhibit PGE(2) production in cytokine-stimulated synovial fibroblasts, it remains unclear how HA suppresses PGE(2) production in activated cells. Furthermore, HA effect on macrophages has rarely been investigated in spite of their contribution to RA joint pathology. This study was aimed to investigate the inhibitory mechanism of HA on lipopolysaccharide (LPS)-stimulated PGE(2) production in U937 human macrophages. Stimulation of U937 macrophages with LPS enhanced PGE(2) production in association with increased protein levels of cyclooxygenase-2 (COX-2). Pretreatment with HA of 2,700 kDa resulted in suppression of the LPS-mediated induction of COX-2, leading to a decrease in PGE(2) production. Likewise, the LPS-stimulated PGE(2) production was inhibited by the pretreatment with a specific COX2 inhibitor, NS-398, or a specific inhibitor of nuclear factor (NF)-kappaB, BAY11-7085. HA also decreased the degree of phosphorylation and nuclear translocation of NF-kappaB enhanced by LPS. Fluorescence cytochemistry demonstrated that HA bound to CD44, the principal HA receptor, on U937 macrophages. Anti-CD44 antibody reversed the inhibitory effects of HA on the LPS-mediated increase in PGE(2) production, COX-2 induction, and activation of NF-kappaB. These results indicate that HA suppresses the LPS-stimulated PGE(2) production via CD44 through down-regulation of NF-kappaB. Administration of HA into RA joints may decrease PGE(2) production by activated macrophages, which could result in improvement of arthritic pain.

Regulation of ICAM-1 in cells of the monocyte/macrophage system in microgravity.

PubMed

Paulsen, Katrin; Tauber, Svantje; Dumrese, Claudia; Bradacs, Gesine; Simmet, Dana M; Gölz, Nadine; Hauschild, Swantje; Raig, Christiane; Engeli, Stephanie; Gutewort, Annett; Hürlimann, Eva; Biskup, Josefine; Unverdorben, Felix; Rieder, Gabriela; Hofmänner, Daniel; Mutschler, Lisa; Krammer, Sonja; Buttron, Isabell; Philpot, Claudia; Huge, Andreas; Lier, Hartwin; Barz, Ines; Engelmann, Frank; Layer, Liliana E; Thiel, Cora S; Ullrich, Oliver

2015-01-01

Cells of the immune system are highly sensitive to altered gravity, and the monocyte as well as the macrophage function is proven to be impaired under microgravity conditions. In our study, we investigated the surface expression of ICAM-1 protein and expression of ICAM-1 mRNA in cells of the monocyte/macrophage system in microgravity during clinostat, parabolic flight, sounding rocket, and orbital experiments. In murine BV-2 microglial cells, we detected a downregulation of ICAM-1 expression in clinorotation experiments and a rapid and reversible downregulation in the microgravity phase of parabolic flight experiments. In contrast, ICAM-1 expression increased in macrophage-like differentiated human U937 cells during the microgravity phase of parabolic flights and in long-term microgravity provided by a 2D clinostat or during the orbital SIMBOX/Shenzhou-8 mission. In nondifferentiated U937 cells, no effect of microgravity on ICAM-1 expression could be observed during parabolic flight experiments. We conclude that disturbed immune function in microgravity could be a consequence of ICAM-1 modulation in the monocyte/macrophage system, which in turn could have a strong impact on the interaction with T lymphocytes and cell migration. Thus, ICAM-1 can be considered as a rapid-reacting and sustained gravity-regulated molecule in mammalian cells.

Regulation of ICAM-1 in Cells of the Monocyte/Macrophage System in Microgravity

PubMed Central

Paulsen, Katrin; Tauber, Svantje; Dumrese, Claudia; Bradacs, Gesine; Simmet, Dana M.; Gölz, Nadine; Hauschild, Swantje; Raig, Christiane; Engeli, Stephanie; Gutewort, Annett; Hürlimann, Eva; Biskup, Josefine; Rieder, Gabriela; Hofmänner, Daniel; Mutschler, Lisa; Krammer, Sonja; Philpot, Claudia; Huge, Andreas; Lier, Hartwin; Barz, Ines; Engelmann, Frank; Layer, Liliana E.; Thiel, Cora S.

2015-01-01

Cells of the immune system are highly sensitive to altered gravity, and the monocyte as well as the macrophage function is proven to be impaired under microgravity conditions. In our study, we investigated the surface expression of ICAM-1 protein and expression of ICAM-1 mRNA in cells of the monocyte/macrophage system in microgravity during clinostat, parabolic flight, sounding rocket, and orbital experiments. In murine BV-2 microglial cells, we detected a downregulation of ICAM-1 expression in clinorotation experiments and a rapid and reversible downregulation in the microgravity phase of parabolic flight experiments. In contrast, ICAM-1 expression increased in macrophage-like differentiated human U937 cells during the microgravity phase of parabolic flights and in long-term microgravity provided by a 2D clinostat or during the orbital SIMBOX/Shenzhou-8 mission. In nondifferentiated U937 cells, no effect of microgravity on ICAM-1 expression could be observed during parabolic flight experiments. We conclude that disturbed immune function in microgravity could be a consequence of ICAM-1 modulation in the monocyte/macrophage system, which in turn could have a strong impact on the interaction with T lymphocytes and cell migration. Thus, ICAM-1 can be considered as a rapid-reacting and sustained gravity-regulated molecule in mammalian cells. PMID:25654110

Early T-cell precursor acute lymphoblastic leukaemia in children treated in AIEOP centres with AIEOP-BFM protocols: a retrospective analysis.

PubMed

Conter, Valentino; Valsecchi, Maria Grazia; Buldini, Barbara; Parasole, Rosanna; Locatelli, Franco; Colombini, Antonella; Rizzari, Carmelo; Putti, Maria Caterina; Barisone, Elena; Lo Nigro, Luca; Santoro, Nicola; Ziino, Ottavio; Pession, Andrea; Testi, Anna Maria; Micalizzi, Concetta; Casale, Fiorina; Pierani, Paolo; Cesaro, Simone; Cellini, Monica; Silvestri, Daniela; Cazzaniga, Giovanni; Biondi, Andrea; Basso, Giuseppe

2016-02-01

Early T-cell precursor acute lymphoblastic leukaemia was recently recognised as a distinct leukaemia and reported as associated with poor outcomes. We aimed to assess the outcome of early T-cell precursor acute lymphoblastic leukaemia in patients from the Italian Association of Pediatric Hematology Oncology (AIEOP) centres treated with AIEOP-Berlin-Frankfurt-Münster (AIEOP-BFM) protocols. In this retrospective analysis, we included all children aged from 1 to less than 18 years with early T-cell precursor acute lymphoblastic leukaemia immunophenotype diagnosed between Jan 1, 2008, and Oct 31, 2014, from AIEOP centres. Early T-cell precursors were defined as being CD1a and CD8 negative, CD5 weak positive or negative, and positive for at least one of the following antigens: CD34, CD117, HLADR, CD13, CD33, CD11b, or CD65. Treatment was based on AIEOP-BFM acute lymphoblastic leukaemia 2000 (NCT00613457) or AIEOP-BFM acute lymphoblastic leukaemia 2009 protocols (European Clinical Trials Database 2007-004270-43). The main differences in treatment and stratification of T-cell acute lymphoblastic leukaemia between the two protocols were that in the 2009 protocol only, pegylated L-asparaginase was substituted for Escherichia coli L-asparaginase, patients with prednisone poor response received an additional dose of cyclophosphamide at day 10 of phase IA, and high minimal residual disease at day 15 assessed by flow cytometry was used as a high-risk criterion. Outcomes were assessed in terms of event-free survival, disease-free survival, and overall survival. Early T-cell precursor acute lymphoblastic leukaemia was diagnosed in 49 patients. Compared with overall T-cell acute lymphoblastic leukaemia, it was associated with absence of molecular markers for PCR detection of minimal residual disease in 25 (56%) of 45 patients; prednisone poor response in 27 (55%) of 49 patients; high minimal residual disease at day 15 after starting therapy in 25 (64%) of 39 patients (bone marrow blasts ≥ 10%, by flow cytometry); no complete remission after phase IA in 7 (15%) of 46 patients (bone marrow blasts ≥ 5%, morphologically); and high PCR minimal residual disease (≥ 5 × 10(-4)) at day 33 after starting therapy in 17 (85%) of 20 patients with markers available. Overall, 38 (78%) of 49 patients are in continuous complete remission, including 13 of 18 after haemopoietic stem cell transplantation, with three deaths in induction, five deaths after haemopoietic stem cell transplantation, and three relapses. Severe adverse events in the 2009 study were reported in 10 (30%) of 33 patients with early T-cell precursor acute lymphoblastic leukaemia versus 24 (15%) of 164 patients without early T-cell precursor acute lymphoblastic leukaemia and life-threatening events in induction phase IA occurred in 4 (12%) of 33 patients with early T-cell precursor acute lymphoblastic leukaemia versus 7 (4%) of 164 patients without early T-cell precursor acute lymphoblastic leukaemia. No difference was seen in the subsequent consolidation phase IB of protocol I. Early T-cell precursor acute lymphoblastic leukaemia is characterised by poor early response to conventional induction treatment. Consolidation phase IB, based on cyclophosphamide, 6-mercaptopurine, and ara-C at conventional (non-high) doses is effective in reducing minimal residual disease. Although the number of patients and observational time are limited, patients with early T-cell precursor acute lymphoblastic leukaemia treated with current BFM stratification and treatment strategy have a favourable outcome compared with earlier reports. The role of innovative therapies and haemopoietic stem cell therapy in early T-cell precursor acute lymphoblastic leukaemia needs to be assessed. None. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pentoxifylline and the proteasome inhibitor MG132 induce apoptosis in human leukemia U937 cells through a decrease in the expression of Bcl-2 and Bcl-XL and phosphorylation of p65.

PubMed

Bravo-Cuellar, Alejandro; Hernández-Flores, Georgina; Lerma-Díaz, José Manuel; Domínguez-Rodríguez, Jorge Ramiro; Jave-Suárez, Luis F; De Célis-Carrillo, Ruth; Aguilar-Lemarroy, Adriana; Gómez-Lomeli, Paulina; Ortiz-Lazareno, Pablo Cesar

2013-02-28

In Oncology, the resistance of the cancerous cells to chemotherapy continues to be the principal limitation. The nuclear factor-kappa B (NF-κB) transcription factor plays an important role in tumor escape and resistance to chemotherapy and this factor regulates several pathways that promote tumor survival including some antiapoptotic proteins such as Bcl-2 and Bcl-XL. In this study, we investigated, in U937 human leukemia cells, the effects of PTX and the MG132 proteasome inhibitor, drugs that can disrupt the NF-κB pathway. For this, we evaluated viability, apoptosis, cell cycle, caspases-3, -8, -9, cytochrome c release, mitochondrial membrane potential loss, p65 phosphorylation, and the modification in the expression of pro- and antiapoptotic genes, and the Bcl-2 and Bcl-XL antiapoptotic proteins. The two drugs affect the viability of the leukemia cells in a time-dependent manner. The greatest percentage of apoptosis was obtained with a combination of the drugs; likewise, PTX and MG132 induce G1 phase cell cycle arrest and cleavage of caspases -3,-8, -9 and cytochrome c release and mitochondrial membrane potential loss in U937 human leukemia cells. In these cells, PTX and the MG132 proteasome inhibitor decrease p65 (NF-κB subunit) phosphorylation and the antiapoptotic proteins Bcl-2 and Bcl-XL. We also observed, with a combination of these drugs overexpression of a group of the proapoptotic genes BAX, DIABLO, and FAS while the genes BCL-XL, MCL-1, survivin, IκB, and P65 were downregulated. The two drugs used induce apoptosis per se, this cytotoxicity was greater with combination of both drugs. These observations are related with the caspases -9, -3 cleavage and G1 phase cell cycle arrest, and a decrease in p65 phosphorylation and Bcl-2 and Bcl-XL proteins. As well as this combination of drugs promotes the upregulation of the proapoptotic genes and downregulation of antiapoptotic genes. These observations strongly confirm antileukemic potential.

Comparative proteomic analysis of virulent Korean Mycobacterium tuberculosis K-strain with other mycobacteria strain following infection of U-937 macrophage.

PubMed

Ryoo, Sung Weon; Park, Young Kil; Park, Sue-Nie; Shim, Young Soo; Liew, Hyunjeong; Kang, Seongman; Bai, Gill-Han

2007-06-01

In Korea, the Mycobacterium tuberculosis K-strain is the most prevalent clinical isolates and belongs to the Beijing family. In this study, we conducted comparative porteomics of expressed proteins of clinical isolates of the K-strain with H37Rv, H37Ra as well as the vaccine strain of Mycobacterium bovis BCG following phagocytosis by the human monocytic cell line U-937. Proteins were analyzed by 2-D PAGE and MALDITOF-MS. Two proteins, Mb1363 (probable glycogen phosphorylase GlgP) and MT2656 (Haloalkane dehalogenase LinB) were most abundant after phagocytosis of M. tuberculosis K-strain. This approach provides a method to determine specific proteins that may have critical roles in tuberculosis pathogenesis.

Bioactivity screening and mass spectrometric confirmation for the detection of PPARδ agonists that increase type 1 muscle fibres.

PubMed

Bovee, Toine F H; Blokland, Marco; Kersten, Sander; Hamers, Astrid R M; Heskamp, Henri H; Essers, Martien L; Nielen, Michel W F; van Ginkel, Leendert A

2014-01-01

Sensitive and robust bioassays able to detect nuclear receptor activation are very useful for veterinary and doping control, pharmaceutical industry and environmental scientists. Here, we used bioassays based on human leukemic monocyte lymphoma U937 and human liver hepatocellular carcinoma HepG2 cell lines to detect the ligand-induced activation of the peroxisome proliferator-activated receptor delta (PPARδ). Exposure of U937 cells to the PPARδ agonist GW501516 resulted in a marked increase in mRNA expression of the PPARδ target gene Angptl4 which was quantified by qRT-PCR analysis. Exposure of HepG2 cells transiently transfected with a PPARδ expression plasmid and a PPAR-response element-driven luciferase reporter plasmid to PPARδ agonists GW501516, GW610742 and L-165041 resulted in clear dose-response curves. Although the qRT-PCR resulted in higher fold inductions, the luciferase assay with transfected HepG2 cells is cheaper and quicker and about ten times more sensitive to GW501516 compared to analysis of Angptl4 mRNA expression in U937 cells by qRT-PCR. The HepG2-based luciferase assay was therefore used to screen GW501516-spiked supplements and feed and water samples. After liquid extraction and clean-up by solid phase extraction using a weak anion exchange column, extracts were screened in the HepG2 bioassay followed by confirmation with a newly developed UPLC-MS/MS method, using two transitions for each compound, i.e., for GW501516, 454.07>188.15 (collision energy (CE) 46 V) and 454.07>257.08 (CE 30 V); for GW610742, 472.07>206.2 (CE 48 V) and 472.07>275.08 (CE 30 V); and for L-165041, 401.2>193.15 (CE 26 V) and 401.2>343.2 (CE 20 V).

[An immunological approach to acute myeloid leukaemia].

PubMed

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

2016-04-01

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

Effects of the HIF1 inhibitor, echinomycin, on growth and NOTCH signalling in leukaemia cells.

PubMed

Yonekura, Satoru; Itoh, Mai; Okuhashi, Yuki; Takahashi, Yusuke; Ono, Aya; Nara, Nobuo; Tohda, Shuji

2013-08-01

To examine the effects of echinomycin, a compound that inhibits DNA-binding activity of hypoxia-inducible factor-1 (HIF1), on leukaemia cell growth. Three acute myeloid leukaemia cell lines and three T-lymphoblastic leukaemia cell lines were cultured with echinomycin. Cell growth, mRNA and protein expression levels were examined by WST-1 assay, reverse-transcription polymerase chain reaction and immunoblotting, respectively. HIF1α protein was expressed in all cell lines under normoxia. Treatment with echinomycin suppressed cell growth and induced apoptosis in association with decreased mRNA expression of HIF1 targets, glucose transporter-1 (GLUT1) and B-cell CLL/lymphoma-2 (BCL2). Echinomycin also suppressed the protein expression of NOTCH1, cleaved NOTCH1, v-myc myelocytomatosis viral oncogene homolog (MYC), v-akt murine thymoma viral oncogene homolog-1 (AKT), phosphorylated AKT, mechanistic target of rapamycin (mTOR), and phosphorylated mTOR and increased that of cleaved caspase-3 in some cell lines. Echinomycin suppresses leukaemia cell growth in association with reduced NOTCH1 expression. This is the first report to show that HIF inhibitor treatment suppresses NOTCH1 signalling. HIF inhibitors could be novel candidates for a molecular-targeted therapy against leukaemia.

Use of the bovine leukaemia virus LTR U3 promoter for expressing antisense antiviral RNAs and competitive inhibition of viral infection in cell culture.

PubMed

Shayakhmetov, D; Kovalenko, D; Yurov, G; Borisenko, A; Tikchonenko, T

1997-08-01

Use of viral inducible promoters which can be activated by virus-specific transactivator proteins to drive expression of antisense (as)RNA genes appears to be an attractive approach to inhibit virus infections in vivo. To this end, we have constructed an asRNA gene expressed from the bovine leukaemia virus (BLV) U3 promoter that is complementary to the R-U5 region of the BLV genome. This is the region that is most susceptible to inhibition by asRNA. With plasmid pLU, which expresses the asRNA gene under the control of the BLV U3 promoter, 75% inhibition of virus replication was attained in CC81 cells (the molar ratio of pLU DNA over BLV proviral DNA in the transfection mixture was 5:1). Plasmid pLT, which contains only the BLV U3 promoter without any asRNA-coding region, also efficiently (up to 60%) inhibited virus replication when cotransfected with BLV proviral DNA at a ratio of 20:1. It was suggested that competition between functional and 'empty' viral promoters for the viral transactivator protein p38tax could account for this inhibition. An immunoblotting assay showed that in the presence of nuclear extracts from CC81 cells exogenous BLV p38tax specifically associates with its responsive sequence located in the BLV U3 promoter. Moreover, the additional expression of p38tax in CC81 cells abolishes the inhibitory effect of the empty viral promoter. These observations suggest a new mechanism of BLV inhibition caused, most probably, by sequestering of the viral transactivator protein.

Identification of a role for the nuclear receptor EAR-2 in the maintenance of clonogenic status within the leukemia cell hierarchy

PubMed Central

Ichim, CV; Atkins, HL; Iscove, NN; Wells, RA

2016-01-01

Identification of genes that regulate clonogenicity of acute myelogenous leukemia (AML) cells is hindered by the difficulty of isolating pure populations of cells with defined proliferative abilities. By analyzing the growth of clonal siblings in low passage cultures of the cell line OCI/AML4 we resolved this heterogeneous population into strata of distinct clonogenic potential, permitting analysis of the transcriptional signature of single cells with defined proliferative abilities. By microarray analysis we showed that the expression of the orphan nuclear receptor EAR-2 (NR2F6) is greater in leukemia cells with extensive proliferative capacity than in those that have lost proliferative ability. EAR-2 is expressed highly in long-term hematopoietic stem cells, relative to short-term hematopoietic stem and progenitor cells, and is downregulated in AML cells after induction of differentiation. Exogenous expression of EAR-2 increased the growth of U937 cells and prevented the proliferative arrest associated with terminal differentiation, and blocked differentiation of U937 and 32Dcl3 cells. Conversely, silencing of EAR-2 by short-hairpin RNA initiated terminal differentiation of these cell lines. These data identify EAR-2 as an important factor in the regulation of clonogenicity and differentiation, and establish that analysis of clonal siblings allows the elucidation of differences in gene expression within the AML hierarchy. PMID:21637284

Enhancement of natural killer cell activity in human immunodeficiency virus-infected subjects by in vitro treatment with biologic response modifier OK-432.

PubMed Central

Huang, X L; Fan, Z; Murayama, T; Rinaldo, C

1995-01-01

A decrease in natural killer (NK) cell function has been related to the progression of human immunodeficiency virus (HIV) infection. In the present study, we assessed the ability of a streptococcus-derived biologic response modifier, OK-432, to augment NK lysis of uninfected K562 and U937 cells and HIV-infected U937 cells by peripheral blood mononuclear cells (PBMC) from HIV-seropositive homosexual men. Optimal two- to fourfold increases in lysis of the three targets were observed after pretreatment of PBMC from HIV-negative subjects for 4 h with 2 micrograms of OK-432 per ml. This effect was related primarily to gamma interferon (IFN-gamma) production induced by OK-432 and was not linked to production of tumor necrosis factors alpha and beta or to monocytes in the cultures. The enhancing effect of OK-432 on NK cell function was diminished but still evident in PBMC from subjects with relatively early-phase (< 3-year) HIV infection and high CD4+ cell counts and was lower in subjects with longer-term HIV infection (> 3 years), in association with reduced production of IFN-gamma. Augmentation of NK cell activity in HIV-infected men by OK-432 was comparable to that induced by treatment of cells with 1,000 U of IFN-alpha or interleukin 2 per ml. The data suggest that the NK cell-enhancing effects of OK-432 are at least in part mediated by IFN-gamma and that OK-432 may be effective in treatment of patients with early-phase HIV infection. PMID:7719919

Low-expression of E-cadherin in leukaemia cells causes loss of homophilic adhesion and promotes cell growth.

PubMed

Rao, Qing; Wang, Ji-Ying; Meng, Jihong; Tang, Kejing; Wang, Yanzhong; Wang, Min; Xing, Haiyan; Tian, Zheng; Wang, Jianxiang

2011-09-01

E-cadherin (epithelial cadherin) belongs to the calcium-dependent adhesion molecule superfamily and is implicated in the interactions of haematopoietic progenitors and bone marrow stromal cells. Adhesion capacity to bone marrow stroma was impaired for leukaemia cells, suggesting that a breakdown of adhesive mechanisms governed by an adhesion molecule may exist in leukaemic microenvironment. We previously found that E-cadherin was low expressed in primary acute leukaemia cells compared with normal bone marrow mononuclear cells. In this study, we investigate the functional importance of low E-cadherin expression in leukaemia cell behaviours and investigate its effects in the abnormal interaction of leukaemic cells with stromal cells. After expression of E-cadherin was restored by a demethylating agent in leukaemia cells, E-cadherin-specific adhesion was enhanced. Additionally, siRNA (small interfering RNA)-mediated silencing of E-cadherin in Raji cells resulted in a reduction of cell homophilic adhesion and enhancement of cell proliferation and colony formation. These results suggest that low expression of E-cadherin contributes to the vigorous growth and transforming ability of leukaemic cells.

The Toxoplasma gondii ME-49 strain upregulates levels of A20 that inhibit NF-κB activation and promotes apoptosis in human leukaemia T-cell lines.

PubMed

Chen, Qian; Pang, Min-Hui; Ye, Xiao-Hong; Yang, Guang; Lin, Chen

2018-05-18

Acute T-lymphocyte leukaemia is a form of haematological malignancy with abnormal activation of NF-κB pathway, which results in high expression of A20 and ABIN1, which constitute a negative feedback mechanism for the regulation of NF-κB activation. Clinical studies have found that acute T-lymphocyte leukaemia patients are susceptible to Toxoplasma gondii infection; however, the effect of T. gondii on the proliferation and apoptosis of human leukaemia T-cells remains unclear. Here, we used the T. gondii ME-49 strain to infect human leukaemia T-cell lines Jurkat and Molt-4, to explore the effect of T. gondii on proliferation and apoptosis, which is mediated by NF-κB in human leukaemia T-cells. The Tunel assay was used to detect cell apoptosis. Cell Counting Kit-8 was used to detect cell proliferation viability. The apoptosis level and the expression level of NF-κB related proteins in human leukaemia T-cells were detected by flow cytometry and Western blotting. Western blotting analyses revealed that the T. gondii ME-49 strain increased the expression of A20 and decreased both ABIN1 expression and NF-κB p65 phosphorylation. By constructing a lentiviral-mediated shRNA to knockdown the A20 gene in Jurkat T-cells and Molt-4 T-cells, the apoptosis levels of the two cell lines decreased after T. gondii ME-49 infection, and levels of NF-κB p65 phosphorylation and ABIN1 were higher than in the non-konckdown group. After knockingdown ABIN1 gene expression by constructing the lentiviral-mediated shRNA and transfecting the recombinant expression plasmid containing the ABIN1 gene into two cell lines, apoptosis levels and cleaved caspase-8 expression increased or decreased in response to T. gondii ME-49 infection, respectively. Our data suggest that ABIN1 protects human leukaemia T-cells by allowing them to resist the apoptosis induced by T. gondii ME-49 and that the T. gondii ME-49 strain induces the apoptosis of human leukaemia T-cells via A20-mediated downregulation of ABIN1 expression.

Infrared microspectroscopy of live cells in microfluidic devices (MD-IRMS): toward a powerful label-free cell-based assay.

PubMed

Vaccari, L; Birarda, G; Businaro, L; Pacor, S; Grenci, G

2012-06-05

Until nowadays most infrared microspectroscopy (IRMS) experiments on biological specimens (i.e., tissues or cells) have been routinely carried out on fixed or dried samples in order to circumvent water absorption problems. In this paper, we demonstrate the possibility to widen the range of in-vitro IRMS experiments to vibrational analysis of live cellular samples, thanks to the development of novel biocompatible IR-visible transparent microfluidic devices (MD). In order to highlight the biological relevance of IRMS in MD (MD-IRMS), we performed a systematic exploration of the biochemical alterations induced by different fixation protocols, ethanol 70% and formaldehyde solution 4%, as well as air-drying on U937 leukemic monocytes by comparing their IR vibrational features with the live U937 counterpart. Both fixation and air-drying procedures affected lipid composition and order as well as protein structure at a different extent while they both induced structural alterations in nucleic acids. Therefore, only IRMS of live cells can provide reliable information on both DNA and RNA structure and on their cellular dynamic. In summary, we show that MD-IRMS of live cells is feasible, reliable, and biologically relevant to be recognized as a label-free cell-based assay.

Determination of cellular injury and death thresholds following exposure to high voltage 10ns electrical pulses

NASA Astrophysics Data System (ADS)

Ibey, Bennett L.; Roth, Caleb C.; Bernhard, Joshua A.; Pakhomov, Andrei G.; Wilmink, Gerald J.; Pakhomova, Olga

2011-03-01

Intense, nanosecond-duration electric pulses (nsEP) have been introduced as a novel modality to alter cellular function, with a mechanism of action qualitatively different from micro- and millisecond duration pulses used in electroporation. In this study, we determined the thresholds for plasma membrane injury (within 15 minutes) and cell death (at 24 hours) for 4 different cell types (CHO-K1, HeLa, Jurkat and U937). Plasma membrane injury was measured by flow cytometry using two fluorescent dyes, namely Annexin V-FITC, which binds to phosphatidylserine (PS) upon its externalization (subtle membrane injury), and propidium iodide (PI), which is typically impermeable to the cell, but enters when large pores are formed in the plasma membrane. In all cell types, 10-ns pulses caused phosphatidylserine (PS) externalization at low doses (<150kV/cm and 100 pulses for each cell type) and no PI uptake. Jurkat and U937 cell lines showed substantial cell death without uptake of PI (15 minutes post exposure) suggesting either delayed permeabilization due to swelling, or damage to intracellular components. In CHO-K1 and HeLa cell lines, PI uptake occurred at low doses relative to that necessary to cause cell death suggesting a necrotic death similar to longer pulse exposures. These findings suggest that nanosecond pulses may be beneficial in applications that require selective elimination of specific cell types.

CD10 is a marker for cycling cells with propensity to apoptosis in childhood ALL

PubMed Central

Cutrona, G; Tasso, P; Dono, M; Roncella, S; Ulivi, M; Carpaneto, E M; Fontana, V; Comis, M; Morabito, F; Spinelli, M; Frascella, E; Boffa, L C; Basso, G; Pistoia, V; Ferrarini, M

2002-01-01

CD10 constitutes a favourable prognostic marker for childhood acute lymphoblastic leukaemia. Since correlations between CD10, cell cycle and apoptotic abilities were demonstrated in various cell types, we investigated whether differences existed in the cycling/apoptotic abilities of CD10-positive and CD10-negative B acute lymphoblastic leukaemia cells. Twenty-eight cases of childhood acute lymphoblastic leukaemia (mean age of 6.8 years) were subdivided into two groups according to high (17 cases, 93.2±4.5%, MRFI 211±82 CD10-positive cells) or low (11 cases, 11.5±6.2%, MRFI 10±7 CD10-negative cells) expression of CD10. CD10-positive acute lymphoblastic leukaemia cells were cycling cells with elevated c-myc levels and propensity to apoptosis, whereas CD10-negative acute lymphoblastic leukaemia cells had lower cycling capacities and c-myc levels, and were resistant to apoptosis in vitro. A close correlation between all these properties was demonstrated by the observations that the few CD10-positive cells found in the CD10-negative acute lymphoblastic leukaemia group displayed elevated c-myc and cycling capacities and were apoptosis prone. Moreover, exposure of CD10-positive acute lymphoblastic leukaemia B cells to a peptide nucleic acid anti-gene specific for the second exon of c-myc caused inhibition of c-myc expression and reduced cell cycling and apoptotic abilities as well as decreased CD10 expression. British Journal of Cancer (2002) 86, 1776–1785. doi:10.1038/sj.bjc.6600329 www.bjcancer.com © 2002 Cancer Research UK PMID:12087466

Biochemical and pathophysiological characterization of Helicobacter pylori asparaginase.

PubMed

Shibayama, Keigo; Takeuchi, Hiroaki; Wachino, Jun-Ichi; Mori, Shigetarou; Arakawa, Yoshichika

2011-06-01

Asparaginase was purified from Helicobacter pylori 26695 and its pathophysiological role explored. The K(m) value of asparagine was 9.75 ± 1.81 μM at pH 7.0, and the optimum pH range was broad and around a neutral pH. H. pylori asparaginase converted extracellular asparagine to aspartate. H. pylori cells were unable to take up extracellular asparagine directly. Instead, aspartate produced by the action of the asparaginase was transported into H. pylori cells, where it was partially converted to β-alanine. Asparaginase exhibited striking cytotoxic activity against histiocytic lymphoma cell line U937 cells via asparagine deprivation. The cytotoxic activity of live H. pylori cells against U937 cells was significantly diminished by deletion of the asparaginase gene, indicating that asparaginase functions as a cytotoxic agent of the bacterium. The cytotoxic effect was negligible for gastric epithelial cell line AGS cells, suggesting that the effect differs across host cell types. An asparaginase-deficient mutant strain was significantly less capable of colonizing Mongolian gerbils. Since asparagine depletion by exogenous asparaginase has been shown to suppress lymphocyte proliferation in vivo, the present results suggest that H. pylori asparaginase may be involved in inhibition of normal lymphocyte function at the gastric niche, allowing H. pylori to evade the host immune system. © 2011 The Societies and Blackwell Publishing Asia Pty Ltd.

Mechanism of Hericium erinaceus (Yamabushitake) Mushroom-Induced Apoptosis of U937 Human Monocytic Leukemia Cells

USDA-ARS?s Scientific Manuscript database

Phytochemicals in some foods are a potential source of bioactive safe compounds for cancer chemoprevention. In the present study, we evaluated hot water (HWE), microwaved 50% ethanol (MWE), acidic (ACE), and alkaline (AKE) extracts of the fruit body (sporocarp) of edible Hericium erinaceus (Yamabus...

Flowcytometry – A rapid tool to correlate functional activities of human peripheral blood lymphocytes with their corresponding phenotypes after in vitro stimulation.

PubMed Central

Nirmala, R; Narayanan, PR

2002-01-01

Background While dealing with mixed in vitro lymphocyte cultures one is faced with the problem of relative contributions of different populations to the activity being studied. This is especially true in the controversy relating to the contributions of lymphocyte sub-populations to the Lymphokine Activated Killer (LAK) phenomenon. Flowcytometry can be used to highlight relative contributions of lymphocyte subpopulations towards LAK activity without resorting to difficult purification strategies. We set up long-term in vitro lymphocyte cultures, stimulated them with cytokines IL-2/IL-12, recorded their phenotypic changes and cytotoxic activity against U-937 tumor targets. Results The results indicated that natural killer cells (NK) constituted the predominant proliferating cell population in the cytokine stimulatedcultures. Flowcytometric evidence revealed that CD56+ T cells contributed little to LAK activity against U937 target cells as compared to cells with NK phenotype which were predominantly responsible for spontaneous killing of the tumor targets. The two cytokines, IL-2 and IL-12, had an additive effect on cell proliferation and spontaneous cytotoxicity. Conclusion Flowcytometry can be used to rapidly delineate phenotypic changes in immune cells after stimulation and simultaneously correlate them with corresponding functional activity. This approach may find application as a initial screening tool for studying different types of cells in mixed cultures and their respective activities under stimulatory / inhibitory conditions. PMID:12165101

SiO2-induced release of sVEGFRs from pulmonary macrophages.

PubMed

Chao, Jie; Lv, Yan; Chen, Jin; Wang, Jing; Yao, Honghong

2018-01-01

The inhalation of silicon dioxide (SiO 2 ) particles causes silicosis, a stubborn pulmonary disease that is characterized by alveolar inflammation during the early stage. Soluble cytokine receptors (SCRs) play important roles in regulating inflammation by either attenuating or promoting cytokine signaling. However, the role of SCRs in silicosis remains unknown. Luminex assays revealed increased soluble vascular endothelial growth factor receptor (sVEGFR) family levels in the plasma of silicosis patients. In an enzyme-linked immunosorbent assay (ELISA), cells from the differentiated human monocytic cell line U937 released sVEGFR family proteins after exposure to SiO 2 (50μg/cm 2 ). Further Western blot experiments revealed that VEGFR expression was also elevated in U937 cells. In contrast, levels of sVEGFR family members did not change in the supernatants of human umbilical vein endothelial cells (HUVECs) after exposure to SiO 2 (50μg/cm 2 ). Interestingly, VEGFR expression in HUVECs decreased after SiO 2 treatment. In a scratch assay, HUVECs exhibited cell migration ability, indicating the acquisition of mesenchymal properties. Our findings highlight the important role of sVEGFRs in both inflammation and fibrosis induced by SiO 2 , suggesting a possible mechanism for the fibrogenic effects observed in pulmonary diseases associated with fibrosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Immunocytochemical markers in acute leukaemias diagnosis.

PubMed

Gluzman, D F; Nadgornaya, V A; Sklyarenko, L M; Ivanovskaya, T S; Poludnenko, L Yu; Ukrainskaya, N I

2010-09-01

The study included 1742 patients with acute myeloblastic leukaemias (AML) and acute lymphoblastic leukaemias (ALL), Kyiv city residents and patients from 20 regions of Ukraine. Bone marrow and blood smears were sent at diagnosis to Reference Center. The analysis was based on May-Grünvald-Giemza (MGG) stain and cytochemical reactions (MPO, acNSE, CAE, AP, PAS). Immunocytochemical techniques (APAAP, LSAB) and broad panel of monoclonal antibodies (MoAbs) against lineage specific and differentiation antigens of leukocytes were employed for immunophenotyping of leukemic blast cells directly in blood and bone marrow smears. Different types of AML were defined by the expression of the cell surface and cytoplasmic antigens. Immunocytochemical study was required especially in diagnosing of AML with minimal differentiation, acute megakaryoblastic leukaemia, acute erythroid leukaemia and acute leukaemias of ambiguous lineage. Acute lymphoblastic leukaemias was broadly classified into B-lineage and T-lineage ALL. According to the degree of B-lymphoid differentiation of the blast cells four subtypes of B-lineage ALL were established. T-lineage ALL observed in patients were also divided into four subtypes. Immunocytochemical examination was required to diagnose AL of ambiguous lineage with no clear evidence of lineage differentiation (acute undifferentiated leukaemia) or those with blasts that express markers of more than one lineage (mixed phenotype acute leukaemias).

Multifactorial resistance to aminopeptidase inhibitor prodrug CHR2863 in myeloid leukemia cells: down-regulation of carboxylesterase 1, drug sequestration in lipid droplets and pro-survival activation ERK/Akt/mTOR

PubMed Central

Verbrugge, Sue Ellen; Al, Marjon; Assaraf, Yehuda G.; Kammerer, Sarah; Chandrupatla, Durga M.S.H.; Honeywell, Richard; Musters, Rene P.J.; Giovannetti, Elisa; O'Toole, Tom; Scheffer, George L.; Krige, David; de Gruijl, Tanja D.; Niessen, Hans W.M.; Lems, Willem F.; Kramer, Pieternella A.; Scheper, Rik J.; Cloos, Jacqueline; Ossenkoppele, Gert J.; Peters, Godefridus J.; Jansen, Gerrit

2016-01-01

Aminopeptidase inhibitors are receiving attention as combination chemotherapeutic agents for the treatment of refractory acute myeloid leukemia. However, the factors determining therapeutic efficacy remain elusive. Here we identified the molecular basis of acquired resistance to CHR2863, an orally available hydrophobic aminopeptidase inhibitor prodrug with an esterase-sensitive motif, in myeloid leukemia cells. CHR2863 enters cells by diffusion and is retained therein upon esterase activity-mediated conversion to its hydrophilic active metabolite drug CHR6768, thereby exerting amino acid depletion. Carboxylesterases (CES) serve as candidate prodrug activating enzymes given CES1 expression in acute myeloid leukemia specimens. We established two novel myeloid leukemia sublines U937/CHR2863(200) and U937/CHR2863(5uM), with low (14-fold) and high level (270-fold) CHR2863 resistance. The latter drug resistant cells displayed: (i) complete loss of CES1-mediated drug activation associated with down-regulation of CES1 mRNA and protein, (ii) marked retention/sequestration of the prodrug, (iii) a substantial increase in intracellular lipid droplets, and (iv) a dominant activation of the pro-survival Akt/mTOR pathway. Remarkably, the latter feature coincided with a gain of sensitivity to the mTOR inhibitor rapamycin. These finding delineate the molecular basis of CHR2863 resistance and offer a novel modality to overcome this drug resistance in myeloid leukemia cells. PMID:26496029

3, 3′-Diindolylmethane Exhibits Antileukemic Activity In Vitro and In Vivo through a Akt-Dependent Process

PubMed Central

Gao, Ning; Cheng, Senping; Budhraja, Amit; Liu, E-Hu; Chen, Jieping; Chen, Deying; Yang, Zailin; Luo, Jia; Shi, Xianglin; Zhang, Zhuo

2012-01-01

3,3′-diindolylmethane (DIM), one of the active products derived from Brassica plants, is a promising antitumor agent. The present study indicated that DIM significantly induced apoptosis in U937 human leukemia cells in dose- and time-dependent manners. These events were also noted in other human leukemia cells (Jurkat and HL-60) and primary human leukemia cells (AML) but not in normal bone marrow mononuclear cells. We also found that DIM-induced lethality is associated with caspases activation, myeloid cell leukemia-1 (Mcl-1) down-regulation, p21cip1/waf1 up-regulation, and Akt inactivation accompanied by c-jun NH2-terminal kinase (JNK) activation. Enforced activation of Akt by a constitutively active Akt construct prevented DIM-mediated caspase activation, Mcl-1 down-regulation, JNK activation, and apoptosis. Conversely, DIM lethality was potentiated by the PI3K inhibitor LY294002. Interruption of the JNK pathway by pharmacologic or genetic approaches attenuated DIM-induced caspases activation, Mcl-1 down-regulation, and apoptosis. Lastly, DIM inhibits tumor growth of mouse U937 xenograft, which was related to induction of apoptosis and inactivation of Akt, as well as activation of JNK. Collectively, these findings suggest that DIM induces apoptosis in human leukemia cell lines and primary human leukemia cells, and exhibits antileukemic activity in vivo through Akt inactivation and JNK activation. PMID:22363731

Eliminating malignant cells from cryopreserved ovarian tissue is possible in leukaemia patients.

PubMed

Soares, Michelle; Saussoy, Pascale; Maskens, Mathilde; Reul, Hélène; Amorim, Christiani A; Donnez, Jacques; Dolmans, Marie-Madeleine

2017-07-01

Reimplantation of cryopreserved ovarian tissue (OT) can successfully restore ovarian function in young cancer patients after gonadotoxic treatment. However, for patients with leukaemia, there is a risk of malignant cell transmission. Our objective was to evaluate minimal disseminated disease in OT from leukaemia patients and test a follicle isolation technique to obtain disease-free follicle suspensions. Cryopreserved OT from 12 leukaemia patients was thawed and analysed by histology and long-term xenografting in immunosuppressed mice. In 10 patients, follicles were isolated from OT, and polymerase chain reaction (PCR) was performed on tissue, digested ovarian suspensions and isolated follicle suspensions to investigate leukaemic cell presence. Mean patient age was 17·1 years. An average of 3·2 follicles were isolated per mm² of cortex. Xenografting of OT induced leukaemic masses in 2/12 mice. PCR identified leukaemic cell presence in 66% of OT. Malignant cells were also detected in digested ovarian suspensions. However, none of the follicle samples (>2300 follicles tested) showed any malignant cell presence after washing. This study demonstrates that it is possible to recover large numbers of viable follicles from cryopreserved OT of leukaemia patients. All isolated and washed follicle suspensions tested negative for leukaemic cells, giving leukaemia patients genuine hope of fertility restoration. © 2017 John Wiley & Sons Ltd.

Korean red ginseng extract induces apoptosis and decreases telomerase activity in human leukemia cells.

PubMed

Park, Sang Eun; Park, Cheol; Kim, Sun Hee; Hossain, Mohammad Akbar; Kim, Min Young; Chung, Hae Young; Son, Woo Sung; Kim, Gi-Young; Choi, Yung Hyun; Kim, Nam Deuk

2009-01-21

Korean red ginseng (KRG, Panax ginseng C.A. Meyer Radix rubra) has been used to treat various diseases including cancer. However, the molecular mechanisms responsible for KRG extract induced apoptosis and telomerase inhibition remain unclear. The hot water extract from KRG was used to evaluate the mechanism of induction of apoptosis in U937 human leukemia cells and its effects on cyclooxgenase-2 (COX-2) and telomerase activity. KRG extract treatment to U937 cells resulted in growth inhibition and induction of apoptosis in a concentration-dependent manner as measured by hemacytometer counts, MTT assay, fluorescence microscopy, agarose gel electrophoresis and flow cytometry analysis. The increase in apoptosis was associated with the down-regulation of antiapoptotic Bcl-2, Bcl-X(L), and IAPs family members, and the activation of caspase-3. KRG extract treatment also decreased the expression levels of COX-2 and inducible nitric oxide synthase. Furthermore, KRG extract treatment progressively down-regulated the expression of human telomerase reverse transcriptase, a main determinant of the telomerase enzymatic activity, with inhibiting the expression of c-Myc in a concentration-dependent manner. These results provide important new insights into the possible molecular mechanisms of the anticancer activity of KRG extract.

Complexation of intracellular cyanide by hydroxocobalamin using a human cellular model.

PubMed

Astier, A; Baud, F J

1996-01-01

1. The rational for administering hydroxocobalamin (OHCbl) as an antidote to cyanide poisoning is based on the high affinity of CN ion for cobalt compounds. However, only few data are available on the influence of OHCbl on the intracellular cyanide pool. 2. In human fibroblasts incubated for 10 min with 500 microM of [14C] cyanide, the accumulation ratio was 25 at 37 degrees C (10.45 +/- 1.51 mM) and 11.9 at 4 degrees C. 3. Using the monoblastic U-937 cell line, a rapid uptake of radioactive cyanide was observed with a maximum accumulation ratio of 1.97 at 5 min. 4. A linear relationship between cyanide uptake by U-937 cells and cyanide concentration in incubation medium (10-500 microM; 5 min) was found suggesting a first order process (k = 0.25 min-1). 5. After incubation of fibroblasts with 500 microM of OHCbl, a 75% decrease of intracellular cyanide was observed, with concomittant formation of intracellular cyanocobalamin CNCbl (intracellular/extracellular ratio: 158). 6. These findings suggest that OHCbl is able to penetrate into heavily cyanide loaded cells and to complex cyanide to the non-toxic CNCbl form.

Gynecomastia in a case of hairy cell leukaemia--cladribine induced?

PubMed

Abhyankar, D; Saikia, T; Advani, S

2001-06-01

Gynecomastia is benign enlargement of the male breast and is commonly drug induced. Various drugs are responsible and chemotherapeutic drugs can also cause gynecomastia. Cladribine is now widely used for the treatment of hairy cell leukaemia. We present a case report of development of unilateral gynecomastia in a case of hairy cell leukaemia treated with cladribine and question whether this was induced by the chemotherapy.

Two rare diagnoses during chronic lymphocytic leukaemia follow-up: Kaposi's sarcoma and Merkel cell carcinoma.

PubMed

Dogu, Mehmet H; Sari, Ismail; Hacioglu, Sibel; Degirmencioglu, Serkan; Şen, Nilay; Keskin, Ali

2016-02-01

Chronic lymphocytic leukaemia often has a clinical presentation characterised by increased neoplastic lymphocytes which are mostly mature looking due to B lymphocytes. Increased secondary cancer prevalence has been detected among patients with chronic lymphocytic leukaemia diagnosis. In this report, we present three chronic lymphocytic leukaemia patients who developed secondary rare cancers during their follow-up at our clinic. Case 1: A 54-year-old female patient was diagnosed with stage I chronic lymphocytic leukaemia in 2003 and was diagnosed with Merkel cell carcinoma in February 2013. Case 2: A 66-year-old male patient was diagnosed with stage II chronic lymphocytic leukaemia in 2009 and was diagnosed with Kaposi's sarcoma in March 2013. Case 3: A 77-year-old male patient was diagnosed with stage I chronic lymphocytic leukaemia in 2006 and was diagnosed with Kaposi's sarcoma in 2011. In conclusion, secondary cancers are observed in patients diagnosed with chronic lymphocytic leukaemia. Therefore, follow-up of chronic lymphocytic leukaemia requires additional attention in this context. © The Author(s) 2016.

Cloning and expression of a cDNA coding for a human monocyte-derived plasminogen activator inhibitor.

PubMed

Antalis, T M; Clark, M A; Barnes, T; Lehrbach, P R; Devine, P L; Schevzov, G; Goss, N H; Stephens, R W; Tolstoshev, P

1988-02-01

Human monocyte-derived plasminogen activator inhibitor (mPAI-2) was purified to homogeneity from the U937 cell line and partially sequenced. Oligonucleotide probes derived from this sequence were used to screen a cDNA library prepared from U937 cells. One positive clone was sequenced and contained most of the coding sequence as well as a long incomplete 3' untranslated region (1112 base pairs). This cDNA sequence was shown to encode mPAI-2 by hybrid-select translation. A cDNA clone encoding the remainder of the mPAI-2 mRNA was obtained by primer extension of U937 poly(A)+ RNA using a probe complementary to the mPAI-2 coding region. The coding sequence for mPAI-2 was placed under the control of the lambda PL promoter, and the protein expressed in Escherichia coli formed a complex with urokinase that could be detected immunologically. By nucleotide sequence analysis, mPAI-2 cDNA encodes a protein containing 415 amino acids with a predicted unglycosylated Mr of 46,543. The predicted amino acid sequence of mPAI-2 is very similar to placental PAI-2 (3 amino acid differences) and shows extensive homology with members of the serine protease inhibitor (serpin) superfamily. mPAI-2 was found to be more homologous to ovalbumin (37%) than the endothelial plasminogen activator inhibitor, PAI-1 (26%). Like ovalbumin, mPAI-2 appears to have no typical amino-terminal signal sequence. The 3' untranslated region of the mPAI-2 cDNA contains a putative regulatory sequence that has been associated with the inflammatory mediators.

Cloning and expression of a cDNA coding for a human monocyte-derived plasminogen activator inhibitor.

PubMed Central

Antalis, T M; Clark, M A; Barnes, T; Lehrbach, P R; Devine, P L; Schevzov, G; Goss, N H; Stephens, R W; Tolstoshev, P

1988-01-01

Human monocyte-derived plasminogen activator inhibitor (mPAI-2) was purified to homogeneity from the U937 cell line and partially sequenced. Oligonucleotide probes derived from this sequence were used to screen a cDNA library prepared from U937 cells. One positive clone was sequenced and contained most of the coding sequence as well as a long incomplete 3' untranslated region (1112 base pairs). This cDNA sequence was shown to encode mPAI-2 by hybrid-select translation. A cDNA clone encoding the remainder of the mPAI-2 mRNA was obtained by primer extension of U937 poly(A)+ RNA using a probe complementary to the mPAI-2 coding region. The coding sequence for mPAI-2 was placed under the control of the lambda PL promoter, and the protein expressed in Escherichia coli formed a complex with urokinase that could be detected immunologically. By nucleotide sequence analysis, mPAI-2 cDNA encodes a protein containing 415 amino acids with a predicted unglycosylated Mr of 46,543. The predicted amino acid sequence of mPAI-2 is very similar to placental PAI-2 (3 amino acid differences) and shows extensive homology with members of the serine protease inhibitor (serpin) superfamily. mPAI-2 was found to be more homologous to ovalbumin (37%) than the endothelial plasminogen activator inhibitor, PAI-1 (26%). Like ovalbumin, mPAI-2 appears to have no typical amino-terminal signal sequence. The 3' untranslated region of the mPAI-2 cDNA contains a putative regulatory sequence that has been associated with the inflammatory mediators. Images PMID:3257578

Co-occurrence of biphenotypic acute leukaemia, glucose 6-phosphate dehydrogenase deficiency and haemoglobin E trait in a single child.

PubMed

Mallick, Debkrishna; Thapa, Rajoo; Biswas, Biswajit

2016-02-01

Acute leukaemias occur as the result of clonal expansion subsequent to transformation and arrest at a normal differentiation stage of haematopoietic precursors, which commit to a single lineage, such as myeloid or B-lymphoid or T-lymphoid cells. Biphenotypic acute leukaemia (BAL) constitutes a biologically different group of leukaemia arising from a precursor stem cell and co-expressing more than one lineage specific marker. The present report describes a child with unusual co-occurrence of biphenotypic (B-precursor cell and Myeloid) acute leukaemia, haemoglobin E trait and glucose 6-phosphate dehydrogenase (G6-PD) deficiency. To the best of our knowledge, this constellation of haematological conditions in a single child has never been described before. 2016 BMJ Publishing Group Ltd.

HSV-1-induced activation of NF-κB protects U937 monocytic cells against both virus replication and apoptosis

PubMed Central

Marino-Merlo, Francesca; Papaianni, Emanuela; Medici, Maria Antonietta; Macchi, Beatrice; Grelli, Sandro; Mosca, Claudia; Borner, Christoph; Mastino, Antonio

2016-01-01

The transcription factor nuclear factor-kappa B (NF-κB) is a crucial player of the antiviral innate response. Intriguingly, however, NF-κB activation is assumed to favour herpes simplex virus (HSV) infection rather than restrict it. Apoptosis, a form of innate response to viruses, is completely inhibited by HSV in fully permissive cells, but not in cells incapable to fully sustain HSV replication, such as immunocompetent cells. To resolve the intricate interplay among NF-κB signalling, apoptosis and permissiveness to HSV-1 in monocytic cells, we utilized U937 monocytic cells in which NF-κB activation was inhibited by expressing a dominant-negative IκBα. Surprisingly, viral production was increased in monocytic cells in which NF-κB was inhibited. Moreover, inhibition of NF-κB led to increased apoptosis following HSV-1 infection, associated with lysosomal membrane permeabilization. High expression of late viral proteins and induction of apoptosis occurred in distinct cells. Transcriptional analysis of known innate response genes by real-time quantitative reverse transcription-PCR excluded a contribution of the assayed genes to the observed phenomena. Thus, in monocytic cells NF-κB activation simultaneously serves as an innate process to restrict viral replication as well as a mechanism to limit the damage of an excessive apoptotic response to HSV-1 infection. This finding may clarify mechanisms controlling HSV-1 infection in monocytic cells. PMID:27584793

Lysosomal isoenzyme profiles used to classify a case of acute undifferentiated leukaemia.

PubMed

Eden, O B; Darbyshire, P; Simpson, R M; Besley, G T; Moss, S; Gentle, T

1985-01-01

Lysosomal enzyme activities and isoenzyme profiles were measured in lymphoid and non-lymphoid leukaemic cells from childhood patients. High activities, especially of beta-hexosaminidase and alpha-mannosidase, were associated with leukaemic cells of myeloid or monocytic origin. Leukaemic cells from two children with acute myeloid leukaemia had a relative reduction in the B isoenzyme of beta-hexosaminidase activity, whereas in patients with non T, non B cell acute lymphoblastic leukaemia, intermediate beta-hexosaminidase isoenzymes were expressed. A patient is described on whom conventional marker studies were either negative or equivocal, but lysosomal enzyme markers were consistent with a myeloid leukaemia. This observation was supported by the clinical course of this patient.

Purification and characterization of a novel high molecular weight exotoxin produced by red tide phytoplankton, Alexandrium tamarense.

PubMed

Yamasaki, Yasuhiro; Katsuo, Daisuke; Nakayasu, Seiichiro; Salati, Cristina; Duan, JingJing; Zou, Yanan; Matsuyama, Yukihiko; Yamaguchi, Kenichi; Oda, Tatsuya

2008-01-01

Our recent studies have demonstrated that the aqueous extract prepared from Alexandrium tamarense, a harmful red tide phytoplankton, showed cytotoxicity on Vero cells. In this study, the toxic substance was purified from the culture supernatant of A. tamarense. Based on the gel-filtration profile, the molecular mass of a purified toxin was estimated to be about 1,000 kDa. On sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, a main band with molecular mass of 1,000 kDa was detected with periodic acid-Schiff (PAS) staining, but no protein bands were detected by Coomassie brilliant blue (CBB) protein staining. Sugar composition analysis of the toxin suggested that the toxin contains galactose, fucose, mannose, N-acetylglucosamine, xylose, and other minor saccharides, whereas no significant levels of amino acids were detected by amino acid analysis. These results suggest that the toxin is a polysaccharide-based compound. The toxin showed cytotoxic effects on various cell lines in a concentration-dependent manner. Among the cell lines tested, U937 cells were the most susceptible to the toxin. In U937 cells treated with the toxin, a typical apoptotic nuclear morphological change and DNA fragmentation were observed. This is the first report demonstrating that a polysaccharide-based toxin isolated from red tide phytoplankton can induce apoptotic cell death. (c) 2008 Wiley Periodicals, Inc.

Carfilzomib induces leukaemia cell apoptosis via inhibiting ELK1/KIAA1524 (Elk-1/CIP2A) and activating PP2A not related to proteasome inhibition.

PubMed

Liu, Chun-Yu; Hsieh, Feng-Shu; Chu, Pei-Yi; Tsai, Wen-Chun; Huang, Chun-Teng; Yu, Yuan-Bin; Huang, Tzu-Ting; Ko, Po-Shen; Hung, Man-Hsin; Wang, Wan-Lun; Shiau, Chung-Wai; Chen, Kuen-Feng

2017-06-01

Enhancing the tumour suppressive activity of protein phosphatase 2A (PP2A) has been suggested to be an anti-leukaemic strategy. KIAA1524 (also termed CIP2A), an oncoprotein inhibiting PP2A, is associated with disease progression in chronic myeloid leukaemia and may be prognostic in cytogenetically normal acute myeloid leukaemia. Here we demonstrated that the selective proteasome inhibitor, carfilzomib, induced apoptosis in sensitive primary leukaemia cells and in sensitive leukaemia cell lines, associated with KIAA1524 protein downregulation, increased PP2A activity and decreased p-Akt, but not with the proteasome inhibition effect of carfilzomib. Ectopic expression of KIAA1524, or pretreatment with the PP2A inhibitor, okadaic acid, suppressed carfilzomib-induced apoptosis and KIAA1524 downregulation in sensitive cells, whereas co-treatment with the PP2A agonist, forskolin, enhanced carfilzomib-induced apoptosis in resistant cells. Mechanistically, carfilzomib affected KIAA1524 transcription through disturbing ELK1 (Elk-1) binding to the KIAA1524 promoter. Moreover, the drug sensitivity and mechanism of carfilzomib in xenograft mouse models correlated well with the effects of carfilzomib on KIAA1524 and p-Akt expression, as well as PP2A activity. Our data disclosed a novel drug mechanism of carfilzomib in leukaemia cells and suggests the potential therapeutic implication of KIAA1524 in leukaemia treatment. © 2017 John Wiley & Sons Ltd.

Novel Derivative of Benzofuran Induces Cell Death Mostly by G2/M Cell Cycle Arrest through p53-dependent Pathway but Partially by Inhibition of NF-κB*

PubMed Central

Manna, Sunil K.; Bose, Julie S.; Gangan, Vijay; Raviprakash, Nune; Navaneetha, Thota; Raghavendra, Pongali B.; Babajan, Banaganapalli; Kumar, Chitta S.; Jain, Swatantra K.

2010-01-01

The Dracaena resin is widely used in traditional medicine as an anticancer agent, and benzofuran lignan is the active component. In this report, we provide evidence that the synthetic derivative of benzofuran lignan (Benfur) showed antitumor activities. It induced apoptosis in p53-positive cells. Though it inhibited endotoxin-induced nuclear factor κB (NF-κB) activation in both p53-positive and -negative cells, the activation of caspase 3 was observed in p53-positive cells. It showed partial cell death effect in both p53-positive and -negative cells through inhibition of NF-κB. Cell cycle analysis using flow cytometry showed that treatment with this novel benozofuran lignan derivative to Jurkat T-cells, but not U-937 cells, resulted in a G2/M arrest in a dose- and time-dependent manner. It increased amounts of p21, p27, and cyclin B, but not phospho-Rb through p53 nuclear translocation in Jurkat T-cells, but not in U-937 cells. It inhibited amounts of MDM2 (murine double minute 2) by repressing the transcription factor Sp1, which was also proved in silico. It induced cell death in tumor cells, but not in primary T-cells. Overall, our data suggest that Benfur-mediated cell death is partially dependent upon NF-κB, but predominantly dependent on p53. Thus, this novel benzofuran lignan derivative can be effective chemopreventive or chemotherapeutic agent against malignant T-cells. PMID:20472557

Cell surface expression of beta 2-microglobulin (beta 2m) correlates with stages of differentiation in B cell tumours.

PubMed Central

Jones, R A; Scott, C S; Norfolk, D R; Stark, A N; Child, J A

1987-01-01

Cell surface beta 2-microglobulin (beta 2m) densities of malignant B cells were determined by enzyme immunoassay in 97 cases of immunologically defined lymphoproliferative disease. Absolute beta 2m densities were found to depend on disease category with the lowest levels found on cells from chronic lymphocytic leukaemia (mean = 5.6 ng/10(6) cells, n = 27); atypical chronic lymphocytic leukaemia (mean = 5.9 ng/10(6) cells, n = 8); and prolymphocytoid chronic lymphocytic leukaemia variant (mean = 6.0 ng/10(6) cells, n = 16). beta 2m densities for B non-Hodgkin's lymphoma (n = 14) and B prolymphocytic leukaemia (n = 17) cases were 8.1 and 10.0 ng/10(6) cells, respectively, and the highest densities were found on cells from "late-B cell" tumours (mean = 14.3 ng/10(6) cells). Plasma cells from cases of Ig secreting tumours expressed unexpectedly low beta 2m densities (mean = 9.3 ng/10(6) cells; n = 6). PMID:3108331

Individual and combined tumoricidal effects of dexamethasone and interferons on human leukocyte cell lines.

PubMed

Pan, L Y; Guyre, P M

1988-02-01

We investigated the influence of glucocorticoids on two effects of interferons (IFNs) which are thought to relate to their antitumor actions: cytotoxic activity and induction of HLA antigen expression. We treated human myeloid cell lines (U-937, HL-60, THP-1, K-562, and KG-1a), and T-(MOLT-4) and B- (Daudi) lymphoblastic cell lines with concentrations of IFN-alpha, IFN-gamma, and dexamethasone (Dex) which are commonly achieved in the circulation following therapeutic administration. The results show that for every cell line except Daudi, the greatest inhibition of cell growth occurred when IFN-gamma and Dex treatments were combined. The advantage of combined IFN-gamma and Dex treatment over treatment with either agent alone was most dramatic for the three cell lines (U-937, HL-60, and THP-1) which have monocytoid characteristics. There was also more growth inhibition by the combination of IFN-alpha and Dex than by either agent alone for all seven cell lines tested. The induction of HLA antigen expression by IFN-alpha and IFN-gamma, an effect which could increase recognition of the tumor cells by the immune system, was as great or greater in the presence of Dex as in its absence. These results demonstrate that glucocorticoids do not inhibit, and in some cases enhance, two effects of IFNs that appear to be related to their antitumor actions: inhibition of tumor cell proliferation and enhancement of HLA antigen expression.

Human T-lymphotropic virus type I tax regulates the expression of the human lymphotoxin gene.

PubMed

Tschachler, E; Böhnlein, E; Felzmann, S; Reitz, M S

1993-01-01

Human T-lymphotropic virus type-I (HTLV-I)-infected T-cell lines constitutively produce high levels of lymphotoxin (LT). To analyze the mechanisms that lead to the expression of LT in HTLV-I-infected cell lines, we studied regulatory regions of the human LT promoter involved in the activation of the human LT gene. As determined by deletional analysis, sequences between +137 and -116 (relative to the transcription initiation site) are sufficient to direct expression of a reporter gene in the HTLV-I-infected cell line MT-2. Site-directed mutation of a of the single kappa B-like motif present in the LT promoter region (positions -99 to -89) completely abrogated LT promoter activity in MT-2 cells, suggesting that this site plays a critical role in the activation of the human LT gene. Transfection of LT constructs into HTLV-I-uninfected and -unstimulated Jurkat and U937 cell lines showed little to no activity of the LT promoter. Cotransfection of the same constructs with a tax expression plasmid into Jurkat cells led to detectable promoter activity, which could be significantly increased by stimulation of the cells with phorbol myristate acetate (PMA). Similarly, cotransfection of the LT promoter constructs and the tax expression plasmid into U937 cells led to significant promoter activity upon stimulation with PMA. These data suggest that HTLV-I tax is involved in the upregulation of LT gene expression in HTLV-I-infected cells.

NFκB- and AP-1-mediated DNA looping regulates matrix metalloproteinase-9 transcription in TNF-α-treated human leukemia U937 cells.

PubMed

Chen, Ying-Jung; Chang, Long-Sen

2015-10-01

The aim of this study is to explore the spatial association of critical genomic elements in the effect of TNF-α on matrix metalloproteinase-9 (MMP-9) expression in human leukemia U937 cells. TNF-α up-regulated MMP-9 protein expression and mRNA level in U937 cells, and Akt-mediated-NFκB/p65 activation and JNK-mediated c-Jun activation were proven to be involved in TNF-α-induced MMP-9 up-regulation. Promoter luciferase activity assay revealed that NFκB (nt-600) and AP-1 (nt-79) binding sites were crucial for TNF-α-induced transcription of MMP-9 gene. The results of a chromatin immunoprecipitation assay indicated that TNF-α reduced histone deacetylase-1 (HDAC-1) recruitment but increased p300 (a histone acetyltransferase) recruitment to MMP-9 promoter regions surrounding NFκB and AP-1 binding sites. Consistently, TNF-α increased enrichment of the acetylated histone H3 mark on MMP-9 promoter regions. DNA affinity purification assay revealed that p300 and HDAC1 could bind oligonucleotides containing AP-1/c-Jun and NFκB/p65 binding sites. Chromosome conformation capture assay showed that TNF-α stimulated chromosomal loops in the MMP-9 promoter via NFκB/p65 and AP-1/c-Jun. The p300-associated acetyltransferase activity was crucial for p65/c-Jun-mediated DNA looping, and inhibition of HDAC activity increased the level of DNA looping. Reduction in the level of DNA looping eliminated all TNF-α-stimulated MMP-9 up-regulation. Taken together, our data suggest that p65/c-Jun-mediated DNA looping is involved in TNF-α-induced MMP-9 up-regulation and that the recruitment of p300 or HDAC1 to NFκB and AP-1 binding sites modifies the level of DNA looping. Copyright © 2015 Elsevier B.V. All rights reserved.

ZEB2 drives immature T-cell lymphoblastic leukaemia development via enhanced tumour-initiating potential and IL-7 receptor signalling

PubMed Central

Goossens, Steven; Radaelli, Enrico; Blanchet, Odile; Durinck, Kaat; Van der Meulen, Joni; Peirs, Sofie; Taghon, Tom; Tremblay, Cedric S.; Costa, Magdaline; Ghahremani, Morvarid Farhang; De Medts, Jelle; Bartunkova, Sonia; Haigh, Katharina; Schwab, Claire; Farla, Natalie; Pieters, Tim; Matthijssens, Filip; Van Roy, Nadine; Best, J. Adam; Deswarte, Kim; Bogaert, Pieter; Carmichael, Catherine; Rickard, Adam; Suryani, Santi; Bracken, Lauryn S.; Alserihi, Raed; Canté-Barrett, Kirsten; Haenebalcke, Lieven; Clappier, Emmanuelle; Rondou, Pieter; Slowicka, Karolina; Huylebroeck, Danny; Goldrath, Ananda W.; Janzen, Viktor; McCormack, Matthew P.; Lock, Richard B.; Curtis, David J.; Harrison, Christine; Berx, Geert; Speleman, Frank; Meijerink, Jules P. P.; Soulier, Jean; Van Vlierberghe, Pieter; Haigh, Jody J.

2015-01-01

Early T-cell precursor leukaemia (ETP-ALL) is a high-risk subtype of human leukaemia that is poorly understood at the molecular level. Here we report translocations targeting the zinc finger E-box-binding transcription factor ZEB2 as a recurrent genetic lesion in immature/ETP-ALL. Using a conditional gain-of-function mouse model, we demonstrate that sustained Zeb2 expression initiates T-cell leukaemia. Moreover, Zeb2-driven mouse leukaemia exhibit some features of the human immature/ETP-ALL gene expression signature, as well as an enhanced leukaemia-initiation potential and activated Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signalling through transcriptional activation of IL7R. This study reveals ZEB2 as an oncogene in the biology of immature/ETP-ALL and paves the way towards pre-clinical studies of novel compounds for the treatment of this aggressive subtype of human T-ALL using our Zeb2-driven mouse model. PMID:25565005

Glycometabolic adaptation mediates the insensitivity of drug-resistant K562/ADM leukaemia cells to adriamycin via the AKT-mTOR/c-Myc signalling pathway.

PubMed

Zhang, Xueyan; Ai, Ziying; Chen, Jing; Yi, Juan; Liu, Zhuan; Zhao, Huaishun; Wei, Hulai

2017-04-01

In human leukaemia, resistance to chemotherapy leads to treatment ineffectiveness or failure. Previous studies have indicated that cancers with increased levels of aerobic glycolysis are insensitive to numerous forms of chemotherapy and respond poorly to radiotherapy. Whether glycolysis serves a key role in drug resistance of leukaemia cells remains unclear. The present study systematically investigated aerobic glycolytic alterations and regulation in K562/adriamycin (ADM) multidrug‑resistant (MDR) and ADM‑sensitive K562 leukaemia cells in normoxia, and the association between drug resistance and improper glycometabolism. The cell proliferating activity was assessed with an MTT colorimetric assay, glycolysis, including glucose consumption, lactate export and key‑enzyme activity was determined by corresponding commercial testing kits. The expression levels of hexokinase‑II (HK‑II), lactate dehydrogenase A (LDHA), glucose transporter‑4 (GLUT‑4), AKT, p‑AKT473/308, mammalian target of rapamycin (mTOR), p‑mTOR, c‑Myc and hypoxia‑inducible factor‑1α (HIF‑1α) were analyzed by western blot or reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). K562/ADM cells exhibited increased glucose consumption and lactate accumulation, increased lactate dehydrogenase, hexokinase and pyruvate kinase activities, and reduced phosphofructokinase activity. In addition, K562/ADM cells expressed significantly more HK‑II and GLUT‑4. Notably, inhibition of glycolysis effectively killed sensitive and resistant leukaemia cells and potently restored the sensitivity of MDR cells to the anticancer agent ADM. The AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin (mTOR) signalling pathway, a crucial regulator of glycometabolic homeostasis, mediated over‑activation and upregulation of c‑Myc expression levels in K562/ADM cells, which directly stimulated glucose consumption and enhanced glycolysis. In conclusion, the present study demonstrated that MDR leukaemia cells exhibit increased aerobic glycolytic activity and that this may be responsible for resistance to chemotherapeutics in leukaemia MDR cells via activation of the AKT‑mTOR‑c‑Myc signalling pathway. Therefore, inhibition of aerobic glycolysis may be a potential therapeutic strategy to efficiently treat multidrug resistance in relapsed or refractory leukaemia and cancers.

Plasmacytoid dendritic cell leukaemia/lymphoma: towards a well defined entity?

PubMed

Garnache-Ottou, Francine; Feuillard, Jean; Saas, Philippe

2007-02-01

CD4(+)/CD56(+) haematodermic neoplasm or 'early' plasmacytoid dendritic cell leukaemia/lymphoma (pDCL) was described as a disease entity in the last World Health Organisation/European Organisation for Research and Treatment of Cancer classification for cutaneous lymphomas. These leukaemia/lymphomas co-express CD4 and CD56 without any other lineage-specific markers and have been identified as arising from plasmacytoid dendritic cells. Despite a fairly homogeneous pattern of markers expressed by most pDCL, numerous distinctive features (e.g. cytological aspects and aberrant marker expression) have been reported. This may be related to the 'lineage-independent developmental' programme of dendritic cells, which may be able to develop from either immature or already committed haematopoietic progenitors. This highlights the need for specific validated markers to diagnose such aggressive leukaemia. Here, we propose--among others (e.g. T-cell leukaemia 1)--blood dendritic cell antigen-2 and high levels of CD123 expression as potential markers. In addition, we propose a multidisciplinary approach including several fields of haematology to improve pDCL diagnosis.

[Monoclonal antibodies in diagnosis of acute leukemias].

PubMed

Krawczyńska, A; Robak, T

1996-01-01

Immunophenotyping has become an essential component for the study of acute myeloblastic (AML) and lymphoblastic (ALL) leukaemias. The recent development of highly specific monoclonal antibodies (Mc Ab) to differentiation antigens (CD) of haematopoetic cells have made it readily available to clinical laboratories in most major hospitals. Immunophenotyping complements standard morphology by providing information on lineage, stage of differentiation and clonality. In addition some of the flow cytometry findings have independent prognostic significance. Monoclonal antibodies useful in defining lineage (B-cell versus T-cell) and stages of differentiation of ALL. It can be also used in identifying characteristic feature of AML and aiding in lineage determination in acute leukaemias that are morphologically undifferentiated. Surface immunophenotyping is especially helpful for recognizing mixed lineage acute leukaemia and diagnosing certain rare entities such as erythroleukaemia (M6), acute megakaryocytic leukaemia (M7) and minimally differentiation acute myeloid leukaemia.

The neuro-steroid, 3β androstene 17α diol exhibits potent cytotoxic effects on human malignant glioma and lymphoma cells through different programmed cell death pathways

PubMed Central

Graf, M R; Jia, W; Loria, R M

2007-01-01

The neuro-steroids 3β-androstene-17α-diol (17α-AED), 3β-androstene-17β-diol (17β-AED), 3β-androstene-7α,-17β-triol (7α-AET) and 3β-androstene-7β,-17β-triol (7β-AET) are metabolites of dehydroepiandrosterone and are produced in neuro-ectodermal tissue. Both epimers of androstenediols (17α-AED and 17β-AED) and androstenetriols (7α-AET and 7β-AET) have markedly different biological functions of their chemical analogue. We investigated the cytotoxic activity of these neuro-steroids on human T98G and U251MG glioblastoma and U937 lymphoma cells. Proliferation studies showed that 17α-AED is the most potent inhibitor, with an IC50 ∼15 μM. For T98G glioma, 90% inhibition was achieved with 25 μM of 17α-AED. Other neuro-steroids tested only marginally suppressed cell proliferation. Reduced cell adherence and viability could be detected after 18 h of 17α-AED exposure. Treatment with 17α-AED induced a significant level of apoptosis in U937 lymphoma cells, but not in the glioma cells. Cytopathology of 17α-AED-treated T98G cells revealed the presence of multiple cytoplasmic vacuoles. Acridine orange staining demonstrated the formation of acidic vesicular organelles in 17α-AED-treated T98G and U251MG, which was inhibited by bafilomycin A1. These findings indicate that 17α-AED bears the most potent cytotoxic activity of the neuro-steroids tested, and the effectiveness may depend on the number of hydroxyls and their position on the androstene molecule. These cytotoxic effects may utilize a non-apoptotic pathway in malignant glioma cells. PMID:17637679

Carcinocythaemia (carcinoma cell leukaemia) in a dog: an acute leukaemia-like picture due to metastatic carcinoma.

PubMed

Amati, M; Miele, F; Avallone, G; Banco, B; Bertazzolo, W

2012-08-01

An eight-year-old entire female boxer was presented with a two-week history of anorexia and lethargy and two-day history of unilateral left epistaxis. Clinical findings and laboratory test results suggested disseminated intravascular coagulation. On blood smear evaluation, occasional large epithelioid-like unclassified cells were detected. Occasionally these cells were organised in small clusters. Bone marrow examination revealed a marked infiltration by a malignant population of the same epithelioid-like cells. The dog was euthanased because of the guarded prognosis. Following histology and immunohistochemistry, a widespread undifferentiated carcinoma of unknown primary origin was diagnosed. To the authors' knowledge, this is the first case of carcinoma cell leukaemia reported in a dog. Carcinoma cell leukaemia is a rare oncological condition previously described in humans, characterised by non-haematopoietic neoplastic cells in peripheral blood. © 2012 British Small Animal Veterinary Association.

Increased expression of human leucocyte antigen class I free heavy chains on monocytes of patients with spondyloarthritis and cells transfected with HLA-B27.

PubMed

Ding, Jin; Feng, Yuan; Zheng, Zhao Hui; Li, Xue Yi; Wu, Zhen Biao; Zhu, Ping

2015-02-01

Human leucocyte antigen (HLA)-B27 expression is correlated with spondyloarthritis (SpA), but its role in disease pathogenesis remains unclear. The aim of the study was to determine whether HLA-B27 free heavy chain (FHC) contributes to SpA pathogenesis. Flow cytometry was used to analyse the FHC expression on CD3+ and CD14+ cells in the peripheral blood (PB) and synovial fluid (SF) from SpA patients, healthy controls, and rheumatoid arthritis (RA) patients. Human monocytic U937 cell lines stably expressing enhanced green fluorescence protein (EGFP)/HLA-B27, EGFP/HLA-A2 or EGFP alone were created to further investigate the relation between HLA-B27 and FHC expression. The relative FHC level on CD14+ PB cells was significantly higher in SpA patients than in controls, but lower than on the SF cells of SpA patients. No significant correlation was found for relative FHC expression with HLA-B27 or β2-microglobulin expression. HLA-B27-transfected U937 cells expressed higher FHC levels than either EGFP/HLA-A2- or EGFP-transfected cells. HLA class I FHC expression was significantly increased on monocytes of SpA patients and HLA-B27-transfected cells, implying that FHC, perhaps mostly derived from HLA-B27, plays an important role in SpA pathogenesis. © 2014 John Wiley & Sons Ltd.

Cardiac Glycoside Glucoevatromonoside Induces Cancer Type-Specific Cell Death

PubMed Central

Schneider, Naira F. Z.; Cerella, Claudia; Lee, Jin-Young; Mazumder, Aloran; Kim, Kyung Rok; de Carvalho, Annelise; Munkert, Jennifer; Pádua, Rodrigo M.; Kreis, Wolfgang; Kim, Kyu-Won; Christov, Christo; Dicato, Mario; Kim, Hyun-Jung; Han, Byung Woo; Braga, Fernão C.; Simões, Cláudia M. O.; Diederich, Marc

2018-01-01

Cardiac glycosides (CGs) are natural compounds used traditionally to treat congestive heart diseases. Recent investigations repositioned CGs as potential anticancer agents. To discover novel cytotoxic CG scaffolds, we selected the cardenolide glucoevatromonoside (GEV) out of 46 CGs for its low nanomolar anti-lung cancer activity. GEV presented reduced toxicity toward non-cancerous cell types (lung MRC-5 and PBMC) and high-affinity binding to the Na+/K+-ATPase α subunit, assessed by computational docking. GEV-induced cell death was caspase-independent, as investigated by a multiparametric approach, and culminates in severe morphological alterations in A549 cells, monitored by transmission electron microscopy, live cell imaging and flow cytometry. This non-canonical cell death was not preceded or accompanied by exacerbation of autophagy. In the presence of GEV, markers of autophagic flux (e.g. LC3I-II conversion) were impacted, even in presence of bafilomycin A1. Cell death induction remained unaffected by calpain, cathepsin, parthanatos, or necroptosis inhibitors. Interestingly, GEV triggered caspase-dependent apoptosis in U937 acute myeloid leukemia cells, witnessing cancer-type specific cell death induction. Differential cell cycle modulation by this CG led to a G2/M arrest, cyclin B1 and p53 downregulation in A549, but not in U937 cells. We further extended the anti-cancer potential of GEV to 3D cell culture using clonogenic and spheroid formation assays and validated our findings in vivo by zebrafish xenografts. Altogether, GEV shows an interesting anticancer profile with the ability to exert cytotoxic effects via induction of different cell death modalities. PMID:29545747

Autophagy is an important event for low-dose cytarabine treatment in acute myeloid leukemia cells.

PubMed

Chen, Liyun; Guo, Pei; Zhang, Yunxiang; Li, Xiaoyang; Jia, Peimin; Tong, Jianhua; Li, Junmin

2017-09-01

Cytarabine (Ara-c) has been an important agent in acute myeloid leukemia (AML) treatment for more than 40 years. While, the mechanisms underlying low dose cytarabine (LD Ara-c) is poorly understood. In this study, we investigated the therapeutic effect of LD Ara-C in vitro. U937 and HEL cell lines were treated with increasing dose of Ara-C and showed growth inhibition rates in a time and dose-dependent manner. Treatment with LD Ara-C (50nM) induced a time-dependent increase in expression of microtubule-associated protein light chain 3 (LC3) and beclin1, but degradation of sequestosome1 (p62) in both U937 and HEL cells. Characteristic of autophagosomes appeared after 24h treatment. Meanwhile, deregulation of Akt-mTOR pathway was also detected. When cultured in presence of autophagy inhibitors, autophagy and differentiation was reversed, and cell growth inhibition was also attenuated. Similar phenomenon could also be seen when beclin1 expression was down-regulated. Taken together, we concluded that LD Ara-C can induce autophagy in AML cells and appeared to play an important role in differentiation and death. Down-regulation of Akt-mTOR pathway is involved in these processes. We suggest that cytarabine-induced autophagy is not a pro-survival mechanism, but accounts for its antineoplastic effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Induction of ceruloplasmin synthesis by IFN-gamma in human monocytic cells

NASA Technical Reports Server (NTRS)

Mazumder, B.; Mukhopadhyay, C. K.; Prok, A.; Cathcart, M. K.; Fox, P. L.

1997-01-01

Ceruloplasmin is a 132-kDa glycoprotein abundant in human plasma. It has multiple in vitro activities, including copper transport, lipid pro- and antioxidant activity, and oxidation of ferrous ion and aromatic amines; however, its physiologic role is uncertain. Although ceruloplasmin is synthesized primarily by the liver in adult humans, production by cells of monocytic origin has been reported. We here show that IFN-gamma is a potent inducer of ceruloplasmin synthesis by monocytic cells. Activation of human monoblastic leukemia U937 cells with IFN-gamma increased the production of ceruloplasmin by at least 20-fold. The identity of the protein was confirmed by plasmin fingerprinting. IFN-gamma also increased ceruloplasmin mRNA. Induction followed a 2- to 4-h lag and was partially blocked by cycloheximide, indicating a requirement for newly synthesized factors. Ceruloplasmin induction in monocytic cells was agonist specific, as IL-1, IL-4, IL-6, IFN-alpha, IFN-beta, TNF-alpha, and LPS were completely ineffective. The induction was also cell type specific, as IFN-gamma did not induce ceruloplasmin synthesis in endothelial or smooth muscle cells. In contrast, IFN-gamma was stimulatory in other monocytic cells, including THP-1 cells and human peripheral blood monocytes, and also in HepG2 cells. Ceruloplasmin secreted by IFN-gamma-stimulated U937 cells had ferroxidase activity and was, in fact, the only secreted protein with this activity. Monocytic cell-derived ceruloplasmin may contribute to defense responses via its ferroxidase activity, which may drive iron homeostasis in a direction unfavorable to invasive organisms.

Production of minimally disturbed synchronous cultures of hematopoietic cells

NASA Technical Reports Server (NTRS)

Thornton, Maureen; Eward, Kathryn Leigh; Helmstetter, Charles E.; Edward, K. L. (Principal Investigator)

2002-01-01

A method is describedforproducing sizable quantities of synchronously dividing, minimally disturbed mammalian cells. Cultures were grown immobilized on surfaces such that cell division within the population resulted in the continuous release of synchronous newborn cells. As judged by the quality and duration of synchronous growth, cell size distributions, and DNA compositions, newborn mouse L1210 cells grew with a very high level of synchrony without overt evidence of growth disturbances. The technology should be applicable to a variety of hematopoietic cells, as evidenced by similar results with human MOLT-4 and U937 cell lines.

An immunophenotypic and molecular diagnosis of composite hairy cell leukaemia and chronic lymphocytic leukaemia.

PubMed

Liptrot, Stuart; O' Brien, David; Langabeer, Stephen E; Quinn, Fiona; Mackarel, A Jill; Elder, Patrick; Vandenberghe, Elisabeth; Hayden, Patrick J

2013-12-01

Hairy cell leukaemia (HCL) and chronic lymphocytic leukaemia (CLL) are distinct clinicopathological B cell chronic lymphoproliferative disorders (B-CLPD). Both diseases have characteristic immunophenotypic and molecular features. The co-existence of two B-CLPD is perhaps more common than previously thought but a composite HCL and CLL has been rarely documented. A case is reported in which the morphology, integrated with an extensive immunophenotyping panel, and incorporation of the recently described HCL-associated BRAF V600E mutation, enabled the prompt diagnosis of composite HCL and CLL thus allowing appropriate treatment selection. This case serves to highlight the benefit of a multidisciplinary approach to the diagnosis of bi-clonal B-CLPD.

IRS2 silencing increases apoptosis and potentiates the effects of ruxolitinib in JAK2V617F-positive myeloproliferative neoplasms

PubMed Central

de Melo Campos, Paula; Machado-Neto, João A.; Eide, Christopher A.; Savage, Samantha L.; Scopim-Ribeiro, Renata; da Silva Souza Duarte, Adriana; Favaro, Patricia; Lorand-Metze, Irene; Costa, Fernando F.; Tognon, Cristina E.; Druker, Brian J.; Saad, Sara T. Olalla; Traina, Fabiola

2016-01-01

The recurrent V617F mutation in JAK2 (JAK2V617F) has emerged as the primary contributor to the pathogenesis of myeloproliferative neoplasms (MPN). However, the lack of complete response in most patients treated with the JAK1/2 inhibitor, ruxolitinib, indicates the need for identifying pathways that cooperate with JAK2. Activated JAK2 was found to be associated with the insulin receptor substrate 2 (IRS2) in non-hematological cells. We identified JAK2/IRS2 binding in JAK2V617F HEL cells, but not in the JAK2WT U937 cell line. In HEL cells, IRS2 silencing decreased STAT5 phosphorylation, reduced cell viability and increased apoptosis; these effects were enhanced when IRS2 silencing was combined with ruxolitinib. In U937 cells, IRS2 silencing neither reduced cell viability nor induced apoptosis. IRS1/2 pharmacological inhibition in primary MPN samples reduced cell viability in JAK2V617F-positive but not JAK2WT specimens; combination with ruxolitinib had additive effects. IRS2 expression was significantly higher in CD34+ cells from essential thrombocythemia patients compared to healthy donors, and in JAK2V617F MPN patients when compared to JAK2WT. Our data indicate that IRS2 is a binding partner of JAK2V617F in MPN. IRS2 contributes to increased cell viability and reduced apoptosis in JAK2-mutated cells. Combined pharmacological inhibition of IRS2 and JAK2 may have a potential clinical application in MPN. PMID:26755644

Wu-Tou Decoction in Rheumatoid Arthritis: Integrating Network Pharmacology and In Vivo Pharmacological Evaluation

PubMed Central

Guo, Qingqing; Zheng, Kang; Fan, Danping; Zhao, Yukun; Li, Li; Bian, Yanqin; Qiu, Xuemei; Liu, Xue; Zhang, Ge; Ma, Chaoying; He, Xiaojuan; Lu, Aiping

2017-01-01

Purpose: This study aimed to explore underlying action mechanism of Wu-Tou decoction (WTD) in rheumatoid arthritis (RA) through network pharmacology prediction and experimental verification. Methods: Chemical compounds and human target proteins of WTD as well as RA-related human genes were obtained from TCM Database @ Taiwan, PubChem and GenBank, respectively. Subsequently, molecular networks and canonical pathways presumably involved in the treatment of WTD on RA were generated by ingenuity pathway analysis (IPA) software. Furthermore, experimental validation was carried out with MIP-1β-induced U937 cell model and collagen induced arthritis (CIA) rat model. Results: CCR5 signaling pathway in macrophages was shown to be the top one shared signaling pathway associated with both cell immune response and cytokine signaling. In addition, protein kinase C (PKC) δ and p38 in this pathway were treated as target proteins of WTD in RA. In vitro experiments indicated that WTD inhibited MIP-1β-induced production of TNF-α, MIP-1α, and RANTES as well as phosphorylation of CCR5, PKC δ, and p38 in U937 cells. WTD treatment maintained the inhibitory effects on production of TNF-α and RANTES in MIP-1β-induced U937 cells after CCR5 knockdown. In vivo experiments demonstrated that WTD ameliorated symptoms in CIA rats, decreased the levels of IL-1β, IL-2, IL-6, TNF-α, MIP-1α, MIP-2, RANTES, and IP-10 in serum of CIA rats, as well as mRNA levels of MIP-1α, MIP-2, RANTES, and IP-10 in ankle joints of CIA rats. Furthermore, WTD also lowered the phosphorylation levels of CCR5, PKC δ and p38 in both ankle joints and macrophages in ankle joints from CIA rats. Conclusion: It was demonstrated in this research that WTD played a role in inhibiting inflammatory response in RA which was closely connected with the modulation effect of WTD on CCR5 signaling pathway in macrophages. PMID:28515692

Application of the pMHC Array to Characterise Tumour Antigen Specific T Cell Populations in Leukaemia Patients at Disease Diagnosis.

PubMed

Brooks, Suzanne E; Bonney, Stephanie A; Lee, Cindy; Publicover, Amy; Khan, Ghazala; Smits, Evelien L; Sigurdardottir, Dagmar; Arno, Matthew; Li, Demin; Mills, Ken I; Pulford, Karen; Banham, Alison H; van Tendeloo, Viggo; Mufti, Ghulam J; Rammensee, Hans-Georg; Elliott, Tim J; Orchard, Kim H; Guinn, Barbara-ann

2015-01-01

Immunotherapy treatments for cancer are becoming increasingly successful, however to further improve our understanding of the T-cell recognition involved in effective responses and to encourage moves towards the development of personalised treatments for leukaemia immunotherapy, precise antigenic targets in individual patients have been identified. Cellular arrays using peptide-MHC (pMHC) tetramers allow the simultaneous detection of different antigen specific T-cell populations naturally circulating in patients and normal donors. We have developed the pMHC array to detect CD8+ T-cell populations in leukaemia patients that recognise epitopes within viral antigens (cytomegalovirus (CMV) and influenza (Flu)) and leukaemia antigens (including Per Arnt Sim domain 1 (PASD1), MelanA, Wilms' Tumour (WT1) and tyrosinase). We show that the pMHC array is at least as sensitive as flow cytometry and has the potential to rapidly identify more than 40 specific T-cell populations in a small sample of T-cells (0.8-1.4 x 10(6)). Fourteen of the twenty-six acute myeloid leukaemia (AML) patients analysed had T cells that recognised tumour antigen epitopes, and eight of these recognised PASD1 epitopes. Other tumour epitopes recognised were MelanA (n = 3), tyrosinase (n = 3) and WT1(126-134) (n = 1). One of the seven acute lymphocytic leukaemia (ALL) patients analysed had T cells that recognised the MUC1(950-958) epitope. In the future the pMHC array may be used provide point of care T-cell analyses, predict patient response to conventional therapy and direct personalised immunotherapy for patients.

Hamamelitannin from Hamamelis virginiana inhibits the tumour necrosis factor-alpha (TNF)-induced endothelial cell death in vitro.

PubMed

Habtemariam, Solomon

2002-01-01

The tumour necrosis factor-alpha (TNF) inhibitory activity of hamamelitannin from Hamamelis virginiana was investigated by assessing the TNF-mediated EAhy926 endothelial cell death and adhesiveness to monocytes. Treatment of the cells by TNF (25 ng/ml) and actinomycin D (0.1ng/ml) resulted in significant DNA fragmentation (34+/-0.6, n=4) and cytotoxicity (97+/-4.5%, n=6) following treatment for 8 and 24h, respectively. One to 100 microM concentrations of hamamelitannin inhibited the TNF-mediated endothelial cell death and DNA fragmentation in a dose-dependent manner. One hundred % protection against TNF-induced DNA fragmentation and cytotoxicity was obtained for hamamelitannin concentrations higher than 10 microM. The protective effect of hamamelitannin was comparable with that of a related compound epigallocatechin gallate while gallic acid was a weak protective agent (<40% protection). EAhy926 endothelial cells upregulated (by 4- to 7-fold) the surface expression of intercellular adhesion molecule-1 (ICAM-1) and adhesiveness to monocytic U937 cells after treatment with TNF (0.5ng/ml) for 6 or 24h. Concentrations (1-100 microM) of hamamelitannin that inhibited the TNF-mediated cell death and DNA fragmentation, however, failed to inhibit the TNF-induced ICAM-1 expression and EAhy926 cell adhesiveness to U937 cells. Thus, hamamelitannin inhibits the TNF-mediated endothelial cell death without altering the TNF-induced upregulation of endothelial adhesiveness. The observed anti-TNF activity of hamamelitannin may explain the antihamorrhaegic use of H. virginiana in traditional medicine and its claimed use as a protective agent for UV radiation.

Helium-based cold atmospheric plasma-induced reactive oxygen species-mediated apoptotic pathway attenuated by platinum nanoparticles.

PubMed

Jawaid, Paras; Rehman, Mati Ur; Zhao, Qing Li; Takeda, Keigo; Ishikawa, Kenji; Hori, Masaru; Shimizu, Tadamichi; Kondo, Takashi

2016-09-01

Plasma is generated by ionizing gas molecules. Helium (He)-based cold atmospheric plasma (CAP) was generated using a high-voltage power supply with low-frequency excitation (60 Hz at 7 kV) and He flow at 2 l/min. Platinum nanoparticles (Pt-NPs) are potent antioxidants due to their unique ability to scavenge superoxides and peroxides. These features make them useful for the protection against oxidative stress-associated pathologies. Here, the effects of Pt-NPs on He-CAP-induced apoptosis and the underlying mechanism were examined in human lymphoma U937 cells. Apoptosis was measured after cells were exposed to He-CAP in the presence or absence of Pt-NPs. The effects of combined treatment were determined by observing the changes in intracellular reactive oxygen species (ROS) and both mitochondrial and Fas dependent pathway. The results indicate that Pt-NPs substantially scavenge He-CAP-induced superoxides and peroxides and inhibit all the pathways involved in apoptosis execution. This might be because of the SOD/catalase mimetic effects of Pt-NPs. These results showed that the Pt-NPs can induce He-CAP desensitization in human lymphoma U937 cells. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Subinhibitory Concentrations of Antimicrobial Agents Reduce the Uptake of Legionella pneumophila into Acanthamoeba castellanii and U937 Cells by Altering the Expression of Virulence-Associated Antigens

PubMed Central

Lück, P. Christian; Schmitt, Jürgen W.; Hengerer, Arne; Helbig, Jürgen H.

1998-01-01

We determined the MICs of ampicillin, ciprofloxacin, erythromycin, imipenem, and rifampin for two clinical isolates of Legionella pneumophila serogroup 1 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay and by quantitative culture. To test the influence of subinhibitory concentrations (sub-MICs) of antimicrobial agents on Legionella uptake into Acanthamoeba castellanii and U937 macrophage-like cells, both strains were pretreated with 0.25 MICs of the antibiotics for 24 h. In comparison to that for the untreated control, subinhibitory concentrations of antibiotics significantly reduced Legionella uptake into the host cells. Measurement of the binding of monoclonal antibodies against several Legionella antigens by enzyme-linked immunoassays indicated that sub-MIC antibiotic treatment reduced the expression of the macrophage infectivity potentiator protein (Mip), the Hsp 60 protein, the outer membrane protein (OmpM), an as-yet-uncharacterized protein of 55 kDa, and a few lipopolysaccharide (LPS) epitopes. In contrast, the expression of some LPS epitopes recognized by monoclonal antibodies 8/5 and 30/4 as well as a 45-kDa protein, a 58-kDa protein, and the major outer membrane protein (OmpS) remained unaffected. PMID:9797218

The Recognition of N-Glycans by the Lectin ArtinM Mediates Cell Death of a Human Myeloid Leukemia Cell Line

PubMed Central

Carvalho, Fernanda Caroline; Soares, Sandro Gomes; Tamarozzi, Mirela Barros; Rego, Eduardo Magalhães; Roque-Barreira, Maria-Cristina

2011-01-01

ArtinM, a d-mannose-binding lectin from Artocarpus heterophyllus (jackfruit), interacts with N-glycosylated receptors on the surface of several cells of hematopoietic origin, triggering cell migration, degranulation, and cytokine release. Because malignant transformation is often associated with altered expression of cell surface glycans, we evaluated the interaction of ArtinM with human myelocytic leukemia cells and investigated cellular responses to lectin binding. The intensity of ArtinM binding varied across 3 leukemia cell lines: NB4>K562>U937. The binding, which was directly related to cell growth suppression, was inhibited in the presence of Manα1-3(Manα1-6)Manβ1, and was reverted in underglycosylated NB4 cells. ArtinM interaction with NB4 cells induced cell death (IC50 = 10 µg/mL), as indicated by cell surface exposure of phosphatidylserine and disruption of mitochondrial membrane potential unassociated with caspase activation or DNA fragmentation. Moreover, ArtinM treatment of NB4 cells strongly induced reactive oxygen species generation and autophagy, as indicated by the detection of acidic vesicular organelles in the treated cells. NB4 cell death was attributed to ArtinM recognition of the trimannosyl core of N-glycans containing a ß1,6-GlcNAc branch linked to α1,6-mannose. This modification correlated with higher levels of N-acetylglucosaminyltransferase V transcripts in NB4 cells than in K562 or U937 cells. Our results provide new insights into the potential of N-glycans containing a β1,6-GlcNAc branch linked to α1,6-mannose as a novel target for anti-leukemia treatment. PMID:22132163

Synchrony in human, mouse and bacterial cell cultures--a comparison

NASA Technical Reports Server (NTRS)

Helmstetter, Charles E.; Thornton, Maureen; Romero, Ana; Eward, K. Leigh

2003-01-01

Growth characteristics of synchronous human MOLT-4, human U-937 and mouse L1210 cultures produced with a new minimally-disturbing technology were compared to each other and to synchronous Escherichia coli B/r. Based on measurements of cell concentrations during synchronous growth, synchrony persisted in similar fashion for all cells. Cell size and DNA distributions in the mammalian cultures also progressed synchronously and reproducibly for multiple cell cycles. The results demonstrate that unambiguous multi-cycle synchrony, critical for verifying the absence of significant growth imbalances induced by the synchronization procedure, is feasible with these cell lines, and possibly others.

Targeting SYK kinase-dependent anti-apoptotic resistance pathway in B-lineage acute lymphoblastic leukaemia (ALL) cells with a potent SYK inhibitory pentapeptide mimic.

PubMed

Uckun, Fatih M; Ek, Rauf O; Jan, Shyi-Tai; Chen, Chun-Lin; Qazi, Sanjive

2010-05-01

The present study found that the pentapeptide mimic C-61, targeting the substrate binding P-site of SYK tyrosine kinase acted as a potent inducer of apoptosis in chemotherapy-resistant SYK-expressing primary leukemic B-cell precursors taken directly from relapsed B-precursor leukaemia (BPL) patients (but not SYK-deficient infant pro-B leukaemia cells), exhibited favourable pharmacokinetics in mice and non-human primates, and eradicated in vivo clonogenic leukaemia cells in severe combined immunodeficient mouse xenograft models of chemotherapy-resistant human BPL at dose levels non-toxic to mice and non-human primates. These in vitro and in vivo findings provide proof of principle for effective treatment of chemotherapy-resistant BPL by targeting SYK-dependent anti-apoptotic blast cell survival machinery with a SYK P-Site inhibitor. Further development of C-61 may provide the foundation for therapeutic innovation against chemotherapy-resistant BPL.

Use of polyclonal anti-myeloperoxidase antibody in myeloid lineage determination.

PubMed

Karnik, M P; Nair, C N; Zingde, S M; Gothoskar, B P; Zachariah, L; Barbhaya, S; Advani, S H

1994-12-01

This study reports the production of a rabbit polyclonal antibody to myeloperoxidase (MPO) and its use in ascertaining the myeloid lineage of blasts in leukaemia. Comparison of the immunocytochemical stain using the anti-MPO antibody with the routine cytochemical methodology showed that the former was more sensitive. In all subtypes of acute myeloid leukaemia (AML; 72 patients, M1-M6) greater number of MPO positive blast cells were observed by immunocytochemistry, the highest being in the promyelocytic leukaemia. It was also extremely specific for cells of the myeloid lineage as it did not react with blasts from acute lymphoblastic (50 patients) and megakaryoblastic leukaemias (1 patient). In addition, it proved most useful for the lineage determination of blasts from patients with undifferentiated acute leukaemias (AUL) and those with chronic myeloid leukaemia in blast crisis (CML-BC). Out of 8 patients of AULs, 6 were classified as acute myeloblastic leukaemia due to their reactivity to the anti-MPO antibody. Similarly, out of 12 patients of chronic myeloid leukaemia in blast crisis, blasts from 8 showed reactivity to this antibody and thus could be identified as belonging to the myeloid lineage and/or of the mixed blast crisis type.

The influence of differential processing of procathepsin H on its aminopeptidase activity, secretion and subcellular localization in human cell lines.

PubMed

Rojnik, Matija; Jevnikar, Zala R; Doljak, Bojan; Turk, Samo; Zidar, Nace; Kos, Janko

2012-10-01

Cathepsin H is a unique member of the cysteine cathepsins that acts primarily as an aminopeptidase. Like other cysteine cathepsins, it is synthesized as an inactive precursor and activated by proteolytic removal of its propeptide. Here we demonstrate that, in human cells, the processing of the propeptide is an autocatalytic, multistep process proceeding from an inactive 41kDa pro-form, through a 30kDa intermediate form, to the 28kDa mature form. Tyr87P and Gly90P were identified as the two major endopeptidase cleavage sites, converting the 30kDa form into the mature 28kDa form. The level of processing differs significantly in different human cell lines. In monocyte-derived macrophages U937 and prostate cancer cells PC-3, the 28kDa form is predominant, whereas in osteoblasts HOS the processing from the 30kDa form to the 28kDa form is significantly lower. The aminopeptidase activity of the enzyme and its subcellular localization are independent of the product, however the 30kDa form was not secreted in HOS cells. The activity of the resulting cathepsin H in U937 cells was significantly lower than that in HOS cells, presumably due to the high levels of endogenous cysteine protease inhibitor cystatin F present specifically in this cell line. These results provide an insight into the dependence of human cathepsin H processing and regulation on cell type. Copyright © 2012 Elsevier GmbH. All rights reserved.

Biosynthesis and processing of cathepsin G and neutrophil elastase in the leukemic myeloid cell line U-937.

PubMed

Lindmark, A; Persson, A M; Olsson, I

1990-12-01

The processing of the neutral proteases cathepsin G and neutrophil elastase, normally synthesized in myeloid precursor cells and stored in azurophil granules, were investigated by biosynthetic labeling with 14C-leucine of the monoblastic cell line U-937. The proteases were precipitated with specific antibodies and the immunoprecipitates were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by fluorography. The transfer to lysosomes of newly synthesized proteases was demonstrated in pulse-chase labeling experiments followed by centrifugation of cell homogenates in a Percoll gradient. The presence of a closely spaced polypeptide band-doublet at intermediate gradient density suggested cleavage of the specific aminoterminal pro dipeptide extension before storage in lysosomes. The molecular heterogeneity observed for cathepsin G and neutrophil elastase seemed to be due to modifications occurring after sorting into lysosomes, most likely because of C-terminal processing. Modifications of the secreted enzymes were not detectable by SDS-PAGE. In contrast to other lysosomal enzymes, no phosphorylation was demonstrated. Newly synthesized cathepsin G and neutrophil elastase rapidly became resistant to endoglycosidase H, indicating transport through the medial and trans cisternae of the Golgi complex and conversion to "complex" oligosaccharide side chains. This conversion was inhibited by an agent swainsonine, but translocation from the Golgi complex and secretion were unaffected. The processing described may play a role in activation of the proteases.

Impact of psychostimulants and atomoxetine on the expression of 8-hydroxyguanine glycosylase 1 in human cells.

PubMed

Schmidt, Andreas Johannes; Clement, Hans-Willi; Gebhardt, Stefan; Hemmeter, Ulrich Michael; Schulz, Eberhard; Krieg, Jürgen-Christian; Kircher, Tilo; Heiser, Philip

2010-06-01

Oxidative DNA damage as one sign of reactive oxygen species induced oxidative stress is an important factor in the pathogenesis of various psychiatric disorders. Altered levels of DNA base damage products as well as the expression of the main repair enzyme 8-hydroxyguanine glycosylase 1 have been described. The aim of the present study was to examine the effects of drugs (amphetamine, methylphenidate and atomoxetine) used in the treatment of attention deficit-hyperactivity disorder on the expression of this enzyme via reverse transcriptase-polymerase chain reaction in human neuroblastoma SH-SY5Y and human monocytic U-937 cells at concentrations of 50, 500 and 5,000 ng/ml. We observed decreased expression of this enzyme for all applied substances. In U-937 cells, the significance level was reached after treatment with 5,000 ng/ml amphetamine as well as after treatment with 50, 500 and 5,000 ng/ml atomoxetine. Incubation of SH-SY5Y cells with 50 and 5,000 ng/ml amphetamine and 5,000 ng/ml methylphenidate led to significant decreases of 8-hydroxyguanine glycosylase 1. As a positive correlation between the expression of 8-hydroxyguanine glycosylase 1 and the level of oxidative DNA damage products has been described, we accordingly consider these substances (amphetamine, methylphenidate and atomoxetine) to possibly play a protective role in this process.

Pertussis toxin permeabilization enhances the traversal of Escherichia coli K1, macrophages, and monocytes in a cerebral endothelial barrier model in vitro.

PubMed

Seidel, Gabriela; Böcker, Kathrin; Schulte, Jessica; Wewer, Corinna; Greune, Lilo; Humberg, Verena; Schmidt, M Alexander

2011-03-01

The occasionally severe neurological complications following the human respiratory tract infection 'whooping cough' have been attributed to pertussis toxin (PT) expressed by the causative agent Bordetella pertussis. Disruption of the endothelial blood-brain barrier (BBB) by PT might facilitate the translocation of immune cells and of hematogenous microbial pathogens. To test this hypothesis, we investigated whether PT enhances the traversal of bacteria employing human brain microvascular endothelial cells (HBMEC) as an in vitro endothelial barrier model. PT incubation significantly increased the translocation of Escherichia coli K1 across the HBMEC barrier. Only intercellular E. coli K1 bacteria could be identified by electron microscopy suggesting paracellular translocation. In addition, the migration of differentiated HL60-derived macrophages and of human monocytic U937 cells through PT-treated HBMEC barriers was also enhanced. In comparison to E. coli C600, E. coli K1 showed prolonged survival in translocated HL60-derived and J774 macrophages as well as in U937 monocytes which suggested a contribution of the 'Trojan horse' mechanism. In summary, our findings demonstrate that the PT-induced permeabilization of endothelial barriers enhances the paracellular transmigration of microbes and immune cells. In vivo, this activity might lower the threshold of bacteremia facilitating secondary cerebral infections and the subsequent development of brain pathologies. Copyright © 2010 Elsevier GmbH. All rights reserved.

Restoration of Corticosteroid Sensitivity in Chronic Obstructive Pulmonary Disease by Inhibition of Mammalian Target of Rapamycin.

PubMed

Mitani, Akihisa; Ito, Kazuhiro; Vuppusetty, Chaitanya; Barnes, Peter J; Mercado, Nicolas

2016-01-15

Corticosteroid resistance is a major barrier to the effective treatment of chronic obstructive pulmonary disease (COPD). Several molecular mechanisms have been proposed, such as activations of the phosphoinositide-3-kinase/Akt pathway and p38 mitogen-activated protein kinase. However, the mechanism for corticosteroid resistance is still not fully elucidated. To investigate the role of mammalian target of rapamycin (mTOR) in corticosteroid sensitivity in COPD. The corticosteroid sensitivity of peripheral blood mononuclear cells collected from patients with COPD, smokers, and nonsmoking control subjects, or of human monocytic U937 cells exposed to cigarette smoke extract (CSE), was quantified as the dexamethasone concentration required to achieve 30% inhibition of tumor necrosis factor-α-induced CXCL8 production in the presence or absence of the mTOR inhibitor rapamycin. mTOR activity was determined as the phosphorylation of p70 S6 kinase, using Western blotting. mTOR activity was increased in peripheral blood mononuclear cells from patients with COPD, and treatment with rapamycin inhibited this as well as restoring corticosteroid sensitivity. In U937 cells, CSE stimulated mTOR activity and c-Jun expression, but pretreatment with rapamycin inhibited both and also reversed CSE-induced corticosteroid insensitivity. mTOR inhibition by rapamycin restores corticosteroid sensitivity via inhibition of c-Jun expression, and thus mTOR is a potential novel therapeutic target for COPD.

5'-Triphosphate siRNA targeting MDR1 reverses multi-drug resistance and activates RIG-I-induced immune-stimulatory and apoptotic effects against human myeloid leukaemia cells.

PubMed

Li, Dengzhe; Gale, Robert Peter; Liu, Yanfeng; Lei, Baoxia; Wang, Yuan; Diao, Dongmei; Zhang, Mei

2017-07-01

Multi-drug resistance (MDR), immune suppression and decreased apoptosis are important causes of therapy-failure in leukaemia. Short interfering RNAs (siRNAs) down-regulate gene transcription, have sequence-independent immune-stimulatory effects and synergize with other anti-cancer therapies in some experimental models. We designed a siRNA targeting MDR1 with 5'-triphosphate ends (3p-siRNA-MDR1). Treatment of leukaemia cells with 3p-siRNA-MDR1 down-regulated MDR1 expression, reduced-drug resistance and induced immune and pro-apoptotic effects in drug-resistant HL-60/Adr and K562/Adr human leukaemia cell lines. We show mechanisms-of-action of these effects involve alterations in the anti-viral cytosolic retinoic acid-inducible protein-I (RIG-I; encoded by RIG-I or DDX58) mediated type-I interferon signal induction, interferon-gamma-inducible protein 10 (IP-10; encoded by IP10 or CXCL10) secretion, major histocompatibility complex-I expression (MHC-I) and caspase-mediated cell apoptosis. 3p-siRNA-MDR1 transfection also enhanced the anti-leukaemia efficacy of doxorubicin. These data suggest a possible synergistic role for 3p-siRNA-MDR1 in anti-leukaemia therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inhibition of differentiation of monocyte to macrophages in atherosclerosis by oligomeric proanthocyanidins -In-vivo and in-vitro study.

PubMed

Mohana, Thiruchenduran; Navin, Alukkathara Vijayan; Jamuna, Sanker; Sakeena Sadullah, Mohammed Sadullah; Niranjali Devaraj, Sivasithamparam

2015-08-01

Monocyte to macrophage differentiation is a key event in the progression of atherosclerosis. An understanding on the fundamental molecular mechanisms and the identification of regulatory mechanisms behind this differentiation may aid in the identification of new therapeutic strategies. Inhibition of this phenomenon will form first line of defense in the prevention and treatment of atherosclerosis. In the current study we explored hypercholesterolemia induced monocyte to macrophage differentiation in-vivo (Wistar rats) leading to atherosclerosis and OxyLDL, M-CSF induced monocyte differentiation in-vitro (U937 cells). Oligomeric proanthocyanidin (OPC) isolated from Crataegus oxyacantha was tested for its efficacy in downregulating this differentiation and in preventing atherogenic disturbances. Cholesterol cholic acid diet induced an increased monocyte to macrophage differentiation by upregulating MCP1 and VCAM1 which induced the inflammatory cytokines that further substantiated the monocyte conversion and infiltration into the vascular walls. On addition of OxyLDL and M-CSF to U937 cells, macrophage markers CD36 and CD 68, PPARγ, MMP2 and 9 were elevated, suggesting differentiation. OPC downregulated this differentiation and thus could prevent the initiation of atherosclerosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Lorenz system in the thermodynamic modelling of leukaemia malignancy.

PubMed

Alexeev, Igor

2017-05-01

The core idea of the proposed thermodynamic modelling of malignancy in leukaemia is entropy arising within normal haematopoiesis. Mathematically its description is supposed to be similar to the Lorenz system of ordinary differential equations for simplified processes of heat flow in fluids. The hypothetical model provides a description of remission and relapse in leukaemia as two hierarchical and qualitatively different states of normal haematopoiesis with their own phase spaces. Phase space transition is possible through pitchfork bifurcation, which is considered the common symmetrical scenario for relapse, induced remission and the spontaneous remission of leukaemia. Cytopenia is regarded as an adaptive reaction of haematopoiesis to an increase in entropy caused by leukaemia clones. The following predictions are formulated: a) the percentage of leukaemia cells in marrow as a criterion of remission or relapse is not necessarily constant but is a variable value; b) the probability of remission depends upon normal haematopoiesis reaching bifurcation; c) the duration of remission depends upon the eradication of leukaemia cells through induction or consolidation therapies; d) excessively high doses of chemotherapy in consolidation may induce relapse. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative study of autophagy inhibition by 3MA and CQ on Cytarabine‑induced death of leukaemia cells.

PubMed

Palmeira dos Santos, Caroline; Pereira, Gustavo J S; Barbosa, Christiano M V; Jurkiewicz, Aron; Smaili, Soraya S; Bincoletto, Claudia

2014-06-01

As the molecular mechanisms of Cytarabine,one of the most important drugs used in the leukaemia’s treatment, are only partially understood and the role of autophagy on leukaemia development and treatment is only recently being investigated, in this study, by using Chloroquine (CQ) and 3-methyladenine (3MA) as autophagy inhibitors, we aim to evaluate the contribution of an autophagic mechanism to Cytarabine (AraC)-induced death of HL60 leukaemia cells. Trypan blue exclusion and AnnexinV/PI assays were used to evaluate HL60 cell death under AraC treatment in the presence or absence of 3MA and CQ. Western blotting and immunofluorescence experiments were performed to show the involvement of apoptosis and autophagy protein expressions. Phenotypic characterization of HL60-treated cells was performed by using immunophenotyping. Clonogenic assays were applied to analyse clonal function of HL60-treated cells. We observed that although autophagy inhibition by 3MA, but not CQ, increased the death of HL60 AraC cells after 24 h of treatment, no significant differences between AraC and AraC + 3MA-treated groups were observed by using clonogenic assay. In addition, increased number of immature (CD34(+)/CD38(−)Lin(−/low)) HL60 cells was found in AraC and AraC-3MA groups when compared with control untreated cells. Although AraC anti-leukaemia effects could be potentiated by 3MA autophagy inhibition after 24 h of exposure, leukaemia cell resistance, the main causes of treatment failure, is also promoted by autophagy initial stage impairment by 3MA, denoting the complex role of autophagy in leukaemia cells’ response to chemotherapy.

Carnitine prevents the early mitochondrial damage induced by methylglyoxal bis(guanylhydrazone) in L1210 leukaemia cells.

PubMed

Nikula, P; Ruohola, H; Alhonen-Hongisto, L; Jänne, J

1985-06-01

We previously found that the anti-cancer drug methylglyoxal bis(guanylhydrazone) (mitoguazone) depresses carnitine-dependent oxidation of long-chain fatty acids in cultured mouse leukaemia cells [Nikula, Alhonen-Hongisto, Seppänen & Jänne (1984) Biochem. Biophys. Res. Commun. 120, 9-14]. We have now investigated whether carnitine also influences the development of the well-known mitochondrial damage produced by the drug in L1210 leukaemia cells. Palmitate oxidation was distinctly inhibited in tumour cells exposed to 5 microM-methylglyoxal bis(guanylhydrazone) for only 7 h. Electron-microscopic examination of the drug-exposed cells revealed that more than half of the mitochondria were severely damaged. Similar exposure of the leukaemia cells to the drug in the presence of carnitine not only abolished the inhibition of fatty acid oxidation but almost completely prevented the drug-induced mitochondrial damage. The protection provided by carnitine appeared to depend on the intracellular concentration of methylglyoxal bis(guanylhydrazone), since the mitochondria-sparing effect disappeared at higher drug concentrations.

Polymerisation par plasma a pression atmospherique: Caracterisation des depots et leurs applications en biotechnologies

NASA Astrophysics Data System (ADS)

Girard-Lauriault, Pierre-Luc

Nitrogen (N)-containing polymer surfaces are attractive in numerous technological contexts, for example in biomedical applications. Here, we have used an atmospheric-pressure dielectric barrier discharge (DBD) apparatus to deposit novel families of N-rich plasma polymers, designated PP:N, using mixtures of three different hydrocarbon precursors (methane, ethylene, and acetylene) in nitrogen at varying respective gas flow ratios, typically parts per thousand. In preparation for subsequent cell-surface interaction studies, the first part of this research focuses on the chemical mapping of those materials, with specific attention to (semi)- quantitative analyses of functional groups. Well-established and some lesser-known analytical techniques have been combined to provide the best possible chemical and structural characterisations of these three families of PP:N thin films; namely, X-ray photoelectron spectroscopy (XPS), Near-edge X-ray absorption fine structure (NEXAFS), Fourier transform infrared spectroscopy (FTIR), contact angle goniometry (CAG), and elemental analysis (EA). High, "tunable" total nitrogen content was measured by both XPS and EA (between 6% and 25% by EA, or between 10% and 40% by XPS, which cannot detect hydrogen). Chemical derivatisation with 4-trifluoromethylbenzaldehyde (TFBA) enabled measurements of primary amine concentrations, the functionality of greatest bio-technological interest, which were found to account for 5 % to 20 % of the total bound nitrogen. By combining the above-mentioned complementary methods, we were further able to determine the complete chemical formulae, the degrees of unsaturation, and other major chemical functionalities in PP:N film structures. Several of these features are believed to be without precedents in the literature on hydrocarbon plasma polymers, for example measurements of absolute compositions (including hydrogen), and of unsaturation. It was shown that besides amines, nitriles, isonitriles and imines are the main nitrogenated functional groups in those materials. In a second part of this work, we have studied the interraction of these well-characterised surfaces with living cells. We have first demonstrated the adhesion, on both uniformly coated and micro-patterned PP:N deposits on BOPP, of three different cell types, namely, growth plate and articular chondrocytes, as well as U937 monocytes, the latter of which do not adhere at all to synthetic polymers used in tissue culture. In an effort to gain insight into cell adhesion mechanisms, we conducted a series of experiments where we cultured U937 monocytes on PP:N, as well as on two other families of chemically well-characterised N-rich thin films, the latter deposited by low pressure RF plasma and by vacuum ultra-violet (VUV) photo-polymerisation ("PVP:N" films). It was first shown that there exist sharply-defined ("critical") surface-chemical conditions that are necessary to induce cell adhesion. By comparing the extensively-characterised film chemistries at the " critical " conditions, we have clearly demonstrated the dominant role of primary amines in the cell adhesion mechanism. In the final aspect of this work, quantitative real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) experiments were conducted using U937 cells that had been made to adhere on PP:N and PVP:N materials for up to 24h. We have shown that the adhesion of U937 monocytes to PP:N and PVP:N surfaces induced a transient expression of cytokines, markers of macrophage activation, as well as a sustained expression of PPARgamma and ICAM-I, implicated in the adhesion and retention of monocytes. Keywords: biomaterials; dielectric barrier discharges (DBD); deposition; plasma polymerisation; ESCA/XPS; NEXAFS; FTIR; primary amines; cell adhesion; gene expression.

Comparative genotypic and phenotypic analysis of human peripheral blood monocytes and surrogate monocyte-like cell lines commonly used in metabolic disease research.

PubMed

Riddy, Darren M; Goy, Emily; Delerive, Philippe; Summers, Roger J; Sexton, Patrick M; Langmead, Christopher J

2018-01-01

Monocyte-like cell lines (MCLCs), including THP-1, HL-60 and U-937 cells, are used routinely as surrogates for isolated human peripheral blood mononuclear cells (PBMCs). To systematically evaluate these immortalised cells and PBMCs as model systems to study inflammation relevant to the pathogenesis of type II diabetes and immuno-metabolism, we compared mRNA expression of inflammation-relevant genes, cell surface expression of cluster of differentiation (CD) markers, and chemotactic responses to inflammatory stimuli. Messenger RNA expression analysis suggested most genes were present at similar levels across all undifferentiated cells, though notably, IDO1, which encodes for indoleamine 2,3-dioxygenase and catabolises tryptophan to kynureninase (shown to be elevated in serum from diabetic patients), was not expressed in any PMA-treated MCLC, but present in GM-CSF-treated PBMCs. There was little overall difference in the pattern of expression of CD markers across all cells, though absolute expression levels varied considerably and the correlation between MCLCs and PBMCs was improved upon MCLC differentiation. Functionally, THP-1 and PBMCs migrated in response to chemoattractants in a transwell assay, with varying sensitivity to MCP-1, MIP-1α and LTB-4. However, despite similar gene and CD expression profiles, U-937 cells were functionally impaired as no migration was observed to any chemoattractant. Our analysis reveals that the MCLCs examined only partly replicate the genotypic and phenotypic properties of human PBMCs. To overcome such issues a universal differentiation protocol should be implemented for these cell lines, similar to those already used with isolated monocytes. Although not perfect, in our hands the THP-1 cells represent the closest, simplified surrogate model of PBMCs for study of inflammatory cell migration.

Synthesis, characterization and deepening in the comprehension of the biological action mechanisms of a new nickel complex with antiproliferative activity.

PubMed

Buschini, Annamaria; Pinelli, Silvana; Pellacani, Claudia; Giordani, Federica; Ferrari, Marisa Belicchi; Bisceglie, Franco; Giannetto, Marco; Pelosi, Giorgio; Tarasconi, Pieralberto

2009-05-01

Thiosemicarbazones are versatile organic compounds that present considerable pharmaceutical interest because of a wide range of properties. In our laboratory we synthesised some new metal-complexes with thiosemicarbazones derived from natural aldehydes which showed peculiar biological activities. In particular, a nickel complex [Ni(S-tcitr)(2)] (S-tcitr=S-citronellalthiosemicarbazonate) was observed to induce an antiproliferative effect on U937, a human histiocytic lymphoma cell line, at low concentrations (IC(50)=14.4microM). Therefore, we decided to study the interactions of this molecule with various cellular components and to characterise the induced apoptotic pathway. Results showed that [Ni(S-tcitr)(2)] causes programmed cell death via down-regulation of Bcl-2, alteration of mitochondrial membrane potential and caspase-3 activity, regardless of p53 function. The metal complex is not active on G(0) cells (i.e. fresh leukocytes) but is able to induce perturbation of the cell cycle on stimulated lymphocytes and U937 cells, in which a G(2)/M block was detected. It reaches the nucleus where it induces, at low concentrations (2.5-5.0microM), DNA damage, which could be partially ascribed to oxidative stress. [Ni(S-tcitr)(2)] is moreover able to strongly reduce the telomerase activity. Although the biological target of this metal complex is still unknown, the reported data suggest that [Ni(S-tcitr)(2)] could be a good model for the synthesis of new metal thiosemicarbazones with specific biological activity.

Acidosis Decreases c-Myc Oncogene Expression in Human Lymphoma Cells: A Role for the Proton-Sensing G Protein-Coupled Receptor TDAG8

PubMed Central

Li, Zhigang; Dong, Lixue; Dean, Eric; Yang, Li V.

2013-01-01

Acidosis is a biochemical hallmark of the tumor microenvironment. Here, we report that acute acidosis decreases c-Myc oncogene expression in U937 human lymphoma cells. The level of c-Myc transcripts, but not mRNA or protein stability, contributes to c-Myc protein reduction under acidosis. The pH-sensing receptor TDAG8 (GPR65) is involved in acidosis-induced c-Myc downregulation. TDAG8 is expressed in U937 lymphoma cells, and the overexpression or knockdown of TDAG8 further decreases or partially rescues c-Myc expression, respectively. Acidic pH alone is insufficient to reduce c-Myc expression, as it does not decrease c-Myc in H1299 lung cancer cells expressing very low levels of pH-sensing G protein-coupled receptors (GPCRs). Instead, c-Myc is slightly increased by acidosis in H1299 cells, but this increase is completely inhibited by ectopic overexpression of TDAG8. Interestingly, TDAG8 expression is decreased by more than 50% in human lymphoma samples in comparison to non-tumorous lymph nodes and spleens, suggesting a potential tumor suppressor function of TDAG8 in lymphoma. Collectively, our results identify a novel mechanism of c-Myc regulation by acidosis in the tumor microenvironment and indicate that modulation of TDAG8 and related pH-sensing receptor pathways may be exploited as a new approach to inhibit Myc expression. PMID:24152439

[Streptococcus group B--association with Aerobic vaginitis and ability to human cell lines activation].

PubMed

Romanik, Małgorzata; Kafel, Joanna; Lagergård, Teresa; Martirosian, Gayane

2007-01-01

The aim of this study was to estimate: the frequency of aerobic vaginitis, susceptibility of the GBS isolated from vagina of non-pregnant women with and without cervicitis to selected antibiotics and chemotherapeutics and the proinflammatory cytokines production by HeLa, THP-I, U - 937 cells after stimulation by vaginal GBS. Our results indicated low frequency of the aerobic vaginitis -4.5% among non-pregnant young women and ability of the vaginal GBS to release proinflammatory cytokines by human cell lines in vitro.

Secondary pure erythroid leukaemia in relapsed acute lymphoblastic leukaemia: lineage switch or chemotherapy effect?

PubMed

Gupta, Sanjeev Kumar; Kumar, Rajive; Chharchhodawala, Taher; Kumar, Lalit

2014-05-19

Pure erythroid leukaemia is a rare subtype of acute myeloid leukaemia (AML) and its occurrence at acute lymphoblastic leukaemia (ALL) relapse has not been reported earlier. A 39-year-old man received chemotherapy for Philadelphia-negative B cell ALL. Subsequently, he developed pure erythroid leukaemia with >80% immature erythroid precursors in bone marrow showing block positivity on periodic acid-Schiff stain, expressing CD71, CD34 but lacking CD235a. The interval between exposure to multidrug chemotherapy including cyclophosphamide and AML diagnosis was 2 years and 9 months. No cytogenetic abnormality was detected at the time of relapse. The patient died 2 weeks after starting AML chemotherapy. The relatively narrow time interval (usually 5-10 years) between chemotherapy and AML development and normal karyotype at relapse raises a possibility of lineage switch besides therapy-related AML as the likely pathogenesis. Further exploration of such cases may unravel the pathways responsible for lineage assignment in pluripotent stem cells. 2014 BMJ Publishing Group Ltd.

Retinoic acid induces signal transducer and activator of transcription (STAT) 1, STAT2, and p48 expression in myeloid leukemia cells and enhances their responsiveness to interferons.

PubMed

Matikainen, S; Ronni, T; Lehtonen, A; Sareneva, T; Melén, K; Nordling, S; Levy, D E; Julkunen, I

1997-06-01

IFNs are antiproliferative cytokines that have growth-inhibitory effects on various normal and malignant cells. Therefore, they have been used in the treatment of certain forms of cancer, such as chronic myelogenous leukemia and hairy cell leukemia. However, there is little evidence that IFNs would be effective in the treatment of acute myelogenous leukemia, and molecular mechanisms underlying IFN unresponsiveness have not been clarified. Here we have studied the activation and induction of IFN-specific transcription factors signal transducer and activator of transcription (STAT) 1, STAT2, and p48 in all-trans-retinoic acid (ATRA)-differentiated myeloid leukemia cells using promyelocytic NB4, myeloblastic HL-60, and monoblastic U937 cells as model systems. These cells respond to ATRA by growth inhibition and differentiation. We show that in undifferentiated NB4 cells, 2',5'-oligoadenylate synthetase and MxB gene expression is not activated by IFN-alpha, possibly due to a relative lack of signaling molecules, especially p48 protein. However, during ATRA-induced differentiation, steady-state STAT1, STAT2, and especially p48 mRNA and corresponding protein levels were elevated both in NB4 and U937 cells, apparently correlating to an enhanced responsiveness of these cells to IFNs. ATRA treatment of NB4 cells sensitized them to IFN action as seen by increased IFN-gamma activation site DNA-binding activity or by efficient formation of IFN-alpha-specific ISGF3 complex and subsequent oligoadenylate synthetase and MxB gene expression. Lack of p48 expression could be one of the mechanisms of promyelocytic leukemia cell escape from growth-inhibitory effects of IFN-alpha.

Toxicological effects of three types of silver nanoparticles and their salt precursors acting on human U-937 and HL-60 cells.

PubMed

Barbasz, Anna; Oćwieja, Magdalena; Walas, Stanisław

2017-01-01

The growing popularity of nanomaterials requires a systematic study of their effects on the human body. Silver nanoparticles (AgNPs), due to their antiseptic properties, are used in almost every area of life. The purpose of the study was to examine whether the precursor used for the synthesis of nanoparticles affects their bio-influence and modifies their impact on cells of the human immune system. To compare the effects of precursor silver salts (AgNO 3 , CH 3 COOAg and AgClO 4 ) and corresponding nanoparticles (TAN TAA and TAC) cytotoxicity study was conducted on two cell lines U-937 and HL-60. For both cell lines, silver salts are more toxic than the corresponding nanoparticles. Cell viability after treatment with the two forms of silver (salt/particle) is dependent on silver dose and degree of cells differentiation. Addition of the silver salt of doses greater than 5 mg/L results in decreased cell viability by over 60%, whereas nanoparticles' addition reduces cell viability on average by 30%. On the basis of the determined LD 50 values it can be stated that for the tested cells the most toxic are AgClO 4 and TAC. Production of nitric oxide, which is a mediator of inflammation, is the greatest after treatment of the cells by TAC. Different interactions of studied nanoparticles with albumin has been found and it was shown that addition of albumin to the cells treated by nanoparticles reduces their toxic effects. Obtained by us highly purified, mono-disperse AgNPs exhibit diverse effects relative to the biological systems, depending on the precursor salt used.

Combination of doxorubicin and low-intensity ultrasound causes a synergistic enhancement in cell killing and an additive enhancement in apoptosis induction in human lymphoma U937 cells.

PubMed

Yoshida, Toru; Kondo, Takashi; Ogawa, Ryohei; Feril, Loreto B; Zhao, Qing-Li; Watanabe, Akihiko; Tsukada, Kazuhiro

2008-04-01

Potential clinical use of ultrasound (US) in enhancing the effects of anticancer drugs in the treatment of cancers has been highlighted in previous reports. Increased uptake of drugs by the cancer cells due to US has been suggested as a mechanism. However, the precise mechanism of the enhancement has not yet been elucidated. Here, the combined effects of low-intensity pulsed US and doxorubicin (DOX) on cell killing and apoptosis induction of U937 cells, and mechanisms involved were investigated. Human myelomonocytic lymphoma U937 cells were used for the experiments. Experiments were conducted in 4 groups: (1) non-treated, (2) DOX treated (DOX), (3) US treated (US), and (4) combined (DOX + US). In DOX +US, cells were exposed to 5 microM DOX for 30 min and sonicated by 1 MHz pulsed US (PRF 100 Hz, DF 10%) at intensities of 0.2-0.5 W/cm(2) for 60 s. The cells were washed and incubated for 6 h. The viability was evaluated by Trypan blue dye exclusion test and apoptosis and incorporation of DOX was assessed by flow cytometry. Involvement of sonoporation in molecular incorporation was evaluated using FITC-dextran, hydroxyl radical formation was measured by electron paramagnetic resonance-spin trapping, membrane alteration including lipid peroxidation and membrane fluidity by DOX was evaluated using cis-parinaric acid and perylene fluorescence polarization method, respectively. Synergistic enhancement in cell killing and additive enhancement in induction of apoptosis were observed at and above 0.3 W/cm(2). No enhancement was observed at 0.2 W/cm(2) in cell killing and induction of apoptosis. Hydroxyl radicals formation was detected at and above 0.3 W/cm(2). The radicals were produced more in the DOX + US than US alone. Incorporation of DOX was increased 13% in DOX + US (vs. DOX) at 0.5 W/cm(2). Involvement of sonoporation for increase of drug uptake was suggested by experiment using FITC-labeled dextran. We made the hypothesis that DOX treatment made the cells weaken against the mechanical effect of the US. Although treatment of DOX at 5 microM for 30 min did not affect lipid peroxidation and fluidity of cell membrane significantly, higher concentration and longer treatment of DOX induced the significant alteration of cell membrane. Mechanisms of enhancements could be (1) increase in incorporation of the DOX by US involved with sonoporation, (2) enhancement of the cavitation by DOX. Cavitation is required for the enhancement of the effect of DOX. Although the precise involvement of the membrane modifications by DOX in the enhancement remains to be elucidated, they could be involved in the latent effects.

Alterations in protein glycosylation in PMA-differentiated U-937 cells exposed to mineral particles.

PubMed Central

Trabelsi, N; Greffard, A; Pairon, J C; Bignon, J; Zanetti, G; Fubini, B; Pilatte, Y

1997-01-01

Carbohydrate moieties of cell glycoconjugates play a pivotal role in molecular recognition phenomena involved in the regulation of most biological systems and the changes observed in cell surface carbohydrates during cell activation or differentiation frequently modulate certain cell functions. Consequently, some aspects of macrophage response to particle exposure might conceivably result from alterations in glycosylation. Therefore, the effect of mineral particles on protein glycosylation was investigated in phorbol myristate acetate (PMA)-differentiated U-937. Jacalin, a lectin specific for O-glycosylated structures, showed a global increase in O-glycosylation in particle-treated cells. In contrast, no significant modifications were observed with concanavalin A, a lectin that recognizes certain N-glycosylated structures. The sialic acid-specific lectins Sambucus nigra agglutinin and Maackia amurensis agglutinin and the galactose-specific lectin Ricinus communis agglutinin revealed a complex pattern of alterations in glycoprotein glycosylation after crystalline silica or manganese dioxide treatments. Expression of sialyl Lewis(x), a glycosylated structure implicated in leukocyte trafficking, could not be detected in control or treated cells. This finding was consistent with the decrease in sialyl Lewis(x) expression observed during PMA-induced differentiation. In conclusion, various treatments used in this study induced quantitative as well as qualitative changes in protein glycosylation. Whether these changes are due to glycosidase release or to an alteration in glycosyltransferase expression remains to be determined. The potential functional implications of these changes are currently under investigation. Images Figure 1. A Figure 1. B Figure 2. A Figure 2. B Figure 3. A Figure 3. B Figure 3. C Figure 4. PMID:9400716

6-Shogaol induces apoptosis in human leukemia cells through a process involving caspase-mediated cleavage of eIF2α.

PubMed

Liu, Qun; Peng, Yong-Bo; Zhou, Ping; Qi, Lian-Wen; Zhang, Mu; Gao, Ning; Liu, E-Hu; Li, Ping

2013-11-12

6-Shogaol is a promising antitumor agent isolated from dietary ginger (Zingiber officinale). However, little is known about the efficacy of 6-shogaol on leukemia cells. Here we investigated the underlying mechanism of 6-shogaol induced apoptosis in human leukemia cells in vitro and in vivo. Three leukemia cell lines and primary leukemia cells were used to investigate the apoptosis effect of 6-shogaol. A shotgun approach based on label-free proteome with LC-CHIP Q-TOF MS/MS was employed to identify the cellular targets of 6-shogaol and the differentially expressed proteins were analyzed by bioinformatics protocols. The present study indicated that 6-shogaol selectively induced apoptosis in transformed and primary leukemia cells but not in normal cells. Eukaryotic translation initiation factor 2 alpha (eIF2α), a key regulator in apoptosis signaling pathway, was significantly affected in both Jurkat and U937 proteome profiles. The docking results suggested that 6-shogaol might bind well to eIF2α at Ser51 of the N-terminal domain. Immunoblotting data indicated that 6-shogaol induced apoptosis through a process involving dephosphorylation of eIF2α and caspase activation-dependent cleavage of eIF2α. Furthermore, 6-shogaol markedly inhibited tumor growth and induced apoptosis in U937 xenograft mouse model. The potent anti-leukemia activity of 6-shogaol found both in vitro and in vivo in our study make this compound a potential anti-tumor agent for hematologic malignancies.

Hyperglycemic Conditions Prime Cells for RIP1-dependent Necroptosis*

PubMed Central

LaRocca, Timothy J.; Sosunov, Sergey A.; Shakerley, Nicole L.; Ten, Vadim S.; Ratner, Adam J.

2016-01-01

Necroptosis is a RIP1-dependent programmed cell death (PCD) pathway that is distinct from apoptosis. Downstream effector pathways of necroptosis include formation of advanced glycation end products (AGEs) and reactive oxygen species (ROS), both of which depend on glycolysis. This suggests that increased cellular glucose may prime necroptosis. Here we show that exposure to hyperglycemic levels of glucose enhances necroptosis in primary red blood cells (RBCs), Jurkat T cells, and U937 monocytes. Pharmacologic or siRNA inhibition of RIP1 prevented the enhanced death, confirming it as RIP1-dependent necroptosis. Hyperglycemic enhancement of necroptosis depends upon glycolysis with AGEs and ROS playing a role. Total levels of RIP1, RIP3, and mixed lineage kinase domain-like (MLKL) proteins were increased following treatment with high levels of glucose in Jurkat and U937 cells and was not due to transcriptional regulation. The observed increase in RIP1, RIP3, and MLKL protein levels suggests a potential positive feedback mechanism in nucleated cell types. Enhanced PCD due to hyperglycemia was specific to necroptosis as extrinsic apoptosis was inhibited by exposure to high levels of glucose. Hyperglycemia resulted in increased infarct size in a mouse model of brain hypoxia-ischemia injury. The increased infarct size was prevented by treatment with nec-1s, strongly suggesting that increased necroptosis accounts for exacerbation of this injury in conditions of hyperglycemia. This work reveals that hyperglycemia represents a condition in which cells are extraordinarily susceptible to necroptosis, that local glucose levels alter the balance of PCD pathways, and that clinically relevant outcomes may depend on glucose-mediated effects on PCD. PMID:27129772

6-Shogaol induces apoptosis in human leukemia cells through a process involving caspase-mediated cleavage of eIF2α

PubMed Central

2013-01-01

Background 6-Shogaol is a promising antitumor agent isolated from dietary ginger (Zingiber officinale). However, little is known about the efficacy of 6-shogaol on leukemia cells. Here we investigated the underlying mechanism of 6-shogaol induced apoptosis in human leukemia cells in vitro and in vivo. Methods Three leukemia cell lines and primary leukemia cells were used to investigate the apoptosis effect of 6-shogaol. A shotgun approach based on label-free proteome with LC-CHIP Q-TOF MS/MS was employed to identify the cellular targets of 6-shogaol and the differentially expressed proteins were analyzed by bioinformatics protocols. Results The present study indicated that 6-shogaol selectively induced apoptosis in transformed and primary leukemia cells but not in normal cells. Eukaryotic translation initiation factor 2 alpha (eIF2α), a key regulator in apoptosis signaling pathway, was significantly affected in both Jurkat and U937 proteome profiles. The docking results suggested that 6-shogaol might bind well to eIF2α at Ser51 of the N-terminal domain. Immunoblotting data indicated that 6-shogaol induced apoptosis through a process involving dephosphorylation of eIF2α and caspase activation–dependent cleavage of eIF2α. Furthermore, 6-shogaol markedly inhibited tumor growth and induced apoptosis in U937 xenograft mouse model. Conclusion The potent anti-leukemia activity of 6-shogaol found both in vitro and in vivo in our study make this compound a potential anti-tumor agent for hematologic malignancies. PMID:24215632

Assessment of Human Lung Macrophages After Exposure to Multi-Walled Carbon Nanotubes. Part 1. Cytotoxicity

DTIC Science & Technology

2011-01-01

animals) to gain a better understanding between their physicochemical properties and bio -effects. Keywords: U937 Cell, MWNTs, MWNT-COOH, ROS. 1...complex (i.e., cells vs. whole animals) to gain a better understanding between their physicochemical properties and bio -effects. 4. MATERIAL AND METHODS...Roach, G. A. M. Reynolds, and T. R. Webb, Tox. Sci. 77, 117 (2004). 3. C. W. Lam, J. T. James , R. McCluskey, and R. L. Hunter, Toxicol. Lett. 77, 126

RUNX3 promoter hypermethylation is frequent in leukaemia cell lines and associated with acute myeloid leukaemia inv(16) subtype.

PubMed

Estécio, Marcos R H; Maddipoti, Sirisha; Bueso-Ramos, Carlos; DiNardo, Courtney D; Yang, Hui; Wei, Yue; Kondo, Kimie; Fang, Zhihong; Stevenson, William; Chang, Kun-Sang; Pierce, Sherry A; Bohannan, Zachary; Borthakur, Gautam; Kantarjian, Hagop; Garcia-Manero, Guillermo

2015-05-01

Correlative and functional studies support the involvement of the RUNX gene family in haematological malignancies. To elucidate the role of epigenetics in RUNX inactivation, we evaluated promoter DNA methylation of RUNX1, 2, and 3 in 23 leukaemia cell lines and samples from acute myeloid leukaemia (AML), acute lymphocytic leukaemia (ALL) and myelodysplatic syndromes (MDS) patients. RUNX1 and RUNX2 gene promoters were mostly unmethylated in cell lines and clinical samples. Hypermethylation of RUNX3 was frequent among cell lines (74%) and highly variable among patient samples, with clear association to cytogenetic status. High frequency of RUNX3 hypermethylation (85% of the 20 studied cases) was found in AML patients with inv(16)(p13.1q22) compared to other AML subtypes (31% of the other 49 cases). RUNX3 hypermethylation was also frequent in ALL (100% of the six cases) but low in MDS (21%). In support of a functional role, hypermethylation of RUNX3 was correlated with low levels of protein, and treatment of cell lines with the DNA demethylating agent, decitabine, resulted in mRNA re-expression. Furthermore, relapse-free survival of non-inv(16)(p13.1q22) AML patients without RUNX3 methylation was significantly better (P = 0·016) than that of methylated cases. These results suggest that RUNX3 silencing is an important event in inv(16)(p13.1q22) leukaemias. © 2015 John Wiley & Sons Ltd.

Pattern of childhood leukaemia in University College Hospital, Ibadan.

PubMed

Babatunde, T O; Ogun, G O; Brown, B J; Akang, E E; Aken'Ova, Y A

2014-06-01

Leukaemias are haematological malignancies characterized by unregulated clonal proliferation of haematopoietic cells. To determine the pattern of childhood leukaemia in Ibadan. This was a retrospective study of leukaemia cases diagnosed at the University College Hospital (UCH), Ibadan between January 1991 and December 2010 in children less than 15 years of age. Data obtained was subjected to statistical analysis using the Statistical Package for Social Sciences version 20. There were 64 cases of childhood leukaemia, accounting for 10.2% of childhood cancers seen during this study period. The male to female ratio was 2:1 and modal age group was between 10 and 14 years. Thirty (46.9%) cases were acute lymphoblastic leukaemia (ALL), 22 (34.4%) were acute myelogenous leukaemia (AML) and 12 (18.8%) were unspecified acute leukaemias. There was no case of chronic myeloid or lymphocytic leukaemia. There has been a relative increase in the frequency of leukaemia cases at UCH, Ibadan, which may be largely explained by increased awareness and referrals. There is a need for further collaborative multicentre studies of childhood leukaemias in Nigeria and other developing countries and focused research on childhood leukaemias in order to unravel the aetiology.

Evaluation of the Genetic Response of U937 and Jurkat Cells to 10-Nanosecond Electrical Pulses (nsEP)

DTIC Science & Technology

2016-05-02

signal-regulated kinase (Erk), heat shock 27kDa protein 1 ( HSP27 ), c-Jun N-terminal kinase (JNK), jun proto-oncogene (c-Jun), dual specificity mitogen...the MAPK pathway-associated proteins were significantly increased (Fig 5D). These included ERK1, JNK, ATF2, HSP27 , c-JUN, and p53. At 12 h post

SOX12: a novel potential target for acute myeloid leukaemia.

PubMed

Wan, Haixia; Cai, Jiayi; Chen, Fangyuan; Zhu, Jianyi; Zhong, Jihua; Zhong, Hua

2017-02-01

The role of SRY-related high-mobility-group box (SOX) 12 in leukaemia progression and haematopoiesis remains elusive. This study aimed to examine the expression and function of SOX12 in acute myeloid leukaemia (AML) using human myeloid leukaemia samples and the acute myeloid cell line THP1. Mononuclear cells were isolated from the bone marrow of AML patients and healthy donors. SOX12 expression in haematopoietic cells was evaluated by reverse transcription polymerase chain reaction (RT-PCR). SOX12 short hairpin RNAs (shRNAs) were transduced into THP1 cells, and gene knockdown was confirmed by quantitative RT-PCR and Western blot analysis. SOX12 was preferentially expressed in CD34 + cells in AML patients. The THP1 cells transduced with SOX12 shRNAs exhibited significantly reduced SOX12 expression and cell proliferation. SOX12 knockdown had no effect on apoptosis, but it induced cell cycle arrest at G1 phase and reduced the number of colonies. The transduced THP1 and primary AML cells were reconstituted in non-obese diabetic-severe combined immunodeficient (NOD/SCID) mice, and their numbers were significantly reduced 6-12 weeks after transplantation. The mRNA and protein levels of β-catenin were significantly diminished following SOX12 knockdown, accompanied by a decrease in TCF/Wnt activity. SOX12 may be involved in leukaemia progression by regulating the expression of β-catenin and then interfering with TCF/Wnt pathway, which may be a target for AML. © 2016 John Wiley & Sons Ltd.

Functional activities of acidic isoferritins and lactoferrin in vitro and in vivo.

PubMed

Broxmeyer, H E; Gentile, P; Cooper, S; Lu, L; Juliano, L; Piacibello, W; Meyers, P A; Cavanna, F

1984-01-01

The functional activities of acidic isoferritins (AIF) and lactoferin (LF) were evaluated. The inhibitory activity of AIF (AIFIA) was inactivated by preincubation with a monoclonal antibody (2A4) against AIF, but AIFIA was not inactivated by another monoclonal antibody against AIF (1C5), by a monoclonal antibody (3A5) against basic isoferritins, or by a heteroantiserum (LFT) against basic isoferritins. Monoclonal 2A4 also inactivated the inhibitory activity against colony formation by granulocyte-macrophage (CFU-GM) progenitor cells that was constitutively released by human monocytes or induced by human monocytes in the presence of OKT4+ lymphocytes. In addition to OKT4+ lymphocytes, the release of AIFIA from human monocytes was modulated by iron-saturated human LF and OKT8+ lymphocytes, both of which suppressed the release of AIFIA. Evidence for the physiologic relevance of AIF as a regulator of myelopoiesis was presented, in that human AIF suppressed the numbers of CFU-GM, BFU-E, and CFU-GEMM per femur and the cycling status of these cells in mice recovering from a sublethal dosage of Cytoxan. Abnormalities in LF and AIF interactions were found with cells from a pediatric patient with neutrophilia of unknown etiology that were consistent with the disease manifestations of neutrophilia. Polymorphonuclear neutrophils (PMN) from the patient contained low levels (1%-10% of control) of immunologically reactive LF and the LF found was ineffective as a suppressor molecule for the release of GM-CSF from normal mononuclear blood cells. In addition, the patient's GM-CSF releasing mononuclear blood cells were insensitive to the suppressive effects of purified LF, and colony formation by the patient's CFU-GM, but not BFU-E or CFU-GEMM, were insensitive to the suppressive effects of purified AIF. When the activity of purified AIF was assessed against mouse bone marrow cells under serum-free conditions, it was apparent that serum was not needed for the suppressive activity of AIF and that in some cases, serum actually masked the effects of AIF. Human monoblast cell line U937 was found to be a good model in vitro for the actions of LF and AIF; U937 cells induced for Ia-antigens by human gamma interferon were separated into populations of Ia-antigen+ and Ia-antigen- cells by fluorescence activated cell sorting (FACS), and LF and AIF suppressed colony formation only by the Ia-antigen+ U937 cells. A comparative analysis of bovine and human LF against release of GM-CSF from human mononuclear cells demonstrated that both were active in their iron-saturated form.(ABSTRACT TRUNCATED AT 400 WORDS)

Leukaemia Evoked with 7,8,12-Trimethylbenz(a)Anthracene in Rat. III. Changes in Lymphoid Tissues

PubMed Central

Bird, C. C.; Mainzer, K.

1972-01-01

Profound changes in the level of certain dehydrogenase enzymes were observed in lymphoid tissues of rats involved by erythroblastic stem cell leukaemia. In lymphoid tissues free of leukaemic involvement, activity of malate dehydrogenase (MDH) always exceeded that of lactate dehydrogenase (LDH). In those which contained substantial infiltrates of leukaemic cells, activity of LDH was increased while MDH activity was reduced. In leukaemic spleen significant changes were observed in the molecular forms of LDH; the proportion of LDH-5 (muscle-type LDH) was greatly increased while the other molecular forms were reduced. The spleen of rats with leukaemia exhibited a marked increase in the normal level of aerobic and anaerobic glycolysis but the rate of respiration was unchanged. The terminal stages of stem cell leukaemia in the rat are characterized by wide-spread leukaemic infiltration of liver and other tissues. Lymph node involvement, however, was found to be selective. Coeliac lymph nodes greatly exceeded other lymph node groups in their incidence of leukaemic involvement. It is considered that the selective nature of lymph node involvement in stem cell leukaemia derives from topographical considerations. PMID:5085676

The inherent metastasis of leukaemia and its exploitation by sonodynamic therapy.

PubMed

Trendowski, Matthew

2015-05-01

Nearly all cancers are linked by the inexorable phenotype of metastasis as malignant growths have the capability to spread from their place of origin to distant sites throughout the body. While different cancers may have various propensities to migrate towards specific locations, they are all linked by this unifying principal. Unlike most neoplasms, leukaemia has inherent cell motility as leukocytes are required to move throughout the vascular system, suggesting that no mutations are required for anchorage independent growth. As such, it seems likely that leukaemias are inherently metastatic, endowed with the deadliest phenotype of cancer simply due to cell of origin. This article presents the biology of metastasis development and how leukaemia cells are inherently provided these phenotypic characteristics. It is then proposed how clinicians may be able to exploit the motility of leukaemia and metastatic emboli of other cancer types through an approach known as sonodynamic therapy (SDT), a treatment modality that combines chemotherapeutic agents with ultrasound to preferentially damage malignant cells. As experimental evidence has indicated, SDT is a promising therapeutic approach in need of clinical testing for further validation. Copyright © 2014 The Author. Published by Elsevier Ireland Ltd.. All rights reserved.

SWI/SNF Subunits SMARCA4, SMARCD2 and DPF2 Collaborate in MLL-Rearranged Leukaemia Maintenance.

PubMed

Cruickshank, V Adam; Sroczynska, Patrycja; Sankar, Aditya; Miyagi, Satoru; Rundsten, Carsten Friis; Johansen, Jens Vilstrup; Helin, Kristian

2015-01-01

Alterations in chromatin structure caused by deregulated epigenetic mechanisms collaborate with underlying genetic lesions to promote cancer. SMARCA4/BRG1, a core component of the SWI/SNF ATP-dependent chromatin-remodelling complex, has been implicated by its mutational spectrum as exerting a tumour-suppressor function in many solid tumours; recently however, it has been reported to sustain leukaemogenic transformation in MLL-rearranged leukaemia in mice. Here we further explore the role of SMARCA4 and the two SWI/SNF subunits SMARCD2/BAF60B and DPF2/BAF45D in leukaemia. We observed the selective requirement for these proteins for leukaemic cell expansion and self-renewal in-vitro as well as in leukaemia. Gene expression profiling in human cells of each of these three factors suggests that they have overlapping functions in leukaemia. The gene expression changes induced by loss of the three proteins demonstrate that they are required for the expression of haematopoietic stem cell associated genes but in contrast to previous results obtained in mouse cells, the three proteins are not required for the expression of c-MYC regulated genes.

Haemopoietic stem cell transplantation for acute lymphoblastic leukaemia.

PubMed

Popat, Uday; Carrum, George; Heslop, Helen E

2003-02-01

The majority of children and some adults with acute lymphocytic leukaemia (ALL) can be cured with current intensive chemotherapy regimens. For those patients who relapse or who do not achieve remission, allogeneic haemopoietic stem cell transplantation (HSCT) offers the best chance for long-term disease control. Different sources of haemopoietic stem cells including marrow, peripheral blood, and cord blood are now available and the introduction of subablative regimens has increased the number of patients who are transplant candidates. Relapse remains the major cause of transplant failure and immunotherapy strategies post-transplant to augment the graft versus leukaemia effect are being explored.

Dietary Phenolic Acids Act as Effective Antioxidants in Membrane Models and in Cultured Cells, Exhibiting Proapoptotic Effects in Leukaemia Cells

PubMed Central

Zambonin, Laura; Caliceti, Cristiana; Vieceli Dalla Sega, Francesco; Fiorentini, Diana; Hrelia, Silvana; Landi, Laura; Prata, Cecilia

2012-01-01

Caffeic, syringic, and protocatechuic acids are phenolic acids derived directly from food intake or come from the gut metabolism of polyphenols. In this study, the antioxidant activity of these compounds was at first evaluated in membrane models, where caffeic acid behaved as a very effective chain-breaking antioxidant, whereas syringic and protocatechuic acids were only retardants of lipid peroxidation. However, all three compounds acted as good scavengers of reactive species in cultured cells subjected to exogenous oxidative stress produced by low level of H2O2. Many tumour cells are characterised by increased ROS levels compared with their noncancerous counterparts. Therefore, we investigated whether phenolic acids, at low concentrations, comparable to those present in human plasma, were able to decrease basal reactive species. Results show that phenolic acids reduced ROS in a leukaemia cell line (HEL), whereas no effect was observed in normal cells, such as HUVEC. The compounds exhibited no toxicity to normal cells while they decreased proliferation in leukaemia cells, inducing apoptosis. In the debate on optimal ROS-manipulating strategies in cancer therapy, our work in leukaemia cells supports the antioxidant ROS-depleting approach. PMID:22792417

Differential responses of Mcl-1 in photosensitized epithelial vs lymphoid-derived human cancer cells.

PubMed

Xue, Liang-yan; Chiu, Song-mao; Oleinick, Nancy L

2005-10-20

The antiapoptotic Bcl-2-family proteins, Bcl-2 and Bcl-xL, are recognized phototargets of photodynamic therapy (PDT) with the mitochondrion-targeting phthalocyanine photosensitizer Pc 4. In the present study, we found that myeloid cell leukemia 1 (Mcl-1), another antiapoptotic member of the Bcl-2 family, was not photodamaged in Pc 4-PDT-treated human carcinoma cells MCF-7c3, MDA-MB468, DU145, and A431, although Mcl-1 turnover was observed after exposure of HeLa or MCF-7c3 cells to a supralethal dose of UVC. In contrast, when human lymphoma U937 and Jurkat cells were treated with Pc 4-PDT, staurosporine (STS) or UVC, Mcl-1 was cleaved to generate a 28-kDa fragment over a 2-4 h period. The cleavage of Mcl-1 was accompanied by the activation of caspases-3, -9, and -8. The broad-specificity caspase inhibitor z-VAD-fmk completely blocked Mcl-1 cleavage induced by PDT, STS or UVC, providing evidence for Mcl-1 as a substrate for caspases. Western blot analysis localized Mcl-1 to mitochondria, ER, and cytosol of both MCF-7c3 and U937 cells, suggesting that Mcl-1 protein, unlike Bcl-2 and Bcl-xL, is not a target for Pc 4-PDT, probably due to its localization to sites removed from those of Pc 4 binding. The 28-kDa cleaved fragment of Mcl-1, which has proapoptotic activity, was produced in PDT-treated lymphoid-derived cells, but not in cells of epithelial origin, suggesting that PDT-induced rapid and extensive apoptosis in lymphoma cells may result in part from the sensitivity of their Mcl-1 to caspase cleavage, removing an important negative control on apoptosis.

Enhanced phosphorylation of STAT1 is dependent on PKR signaling in HLA-B27 expressing U937 monocytic cells

PubMed Central

Ruuska, Marja; Sahlberg, Anna S.; Colbert, Robert A.; Granfors, Kaisa; Penttinen, Markus A.

2011-01-01

Objective To study the phosphorylation of STAT1 in HLA-B27-transfected human monocytic cells and the role of signaling molecules PKR and p38 in STAT1 phosphorylation. Methods U937 human monocytic cell transfectants stably expressing wild type HLA-B27 or mutated HLA-B27 heavy chains (HC) with amino acid substitutions in the B pocket were prepared. Mock transfected cells were prepared using the antibiotic resistance vectors (pSV2neo or RSV5neo) alone. PMA differentiated cells were stimulated with LPS or infected with S. enteritidis. Western blotting and flow cytometry were used to detect the phosphorylation and expression levels of STAT1 protein. Specific inhibitors were added in cell culture to study the role of PKR and p38 on STAT1 phosphorylation. Results STAT1 is constitutively highly phosphorylated on tyrosine 701 residue in HLA-B27 positive monocytic cells when compared to control cells, even prior to stimulation with LPS or bacteria. This phenotype is associated with the expression of HLA-B27 HCs that misfold. In addition, phosphorylation of STAT1 is dependent on PKR. Conclusion Our results show that STAT1 tyrosine 701 is constitutively highly phosphorylated in HLA-B27 expressing monocyte-macrophage cell line. Since phosphorylation of tyrosine 701 on STAT1 is sufficient to induce interferon-dependent genes, constitutive activity of this phosphorylation site may lead to overexpression of interferon-dependent genes, as well as other STAT1-dependent genes, in HLA-B27 monocyte-macrophages. Our results offer a mechanism by which B27 expression alone, without any external trigger, is potentially capable of inducing activation of STAT1, a critical regulator of the inflammatory response. PMID:21968657

Comparative DNA microarray analysis of human monocyte derived dendritic cells and MUTZ-3 cells exposed to the moderate skin sensitizer cinnamaldehyde

DOE Office of Scientific and Technical Information (OSTI.GOV)

Python, Francois; Goebel, Carsten; Aeby, Pierre

2009-09-15

The number of studies involved in the development of in vitro skin sensitization tests has increased since the adoption of the EU 7th amendment to the cosmetics directive proposing to ban animal testing for cosmetic ingredients by 2013. Several studies have recently demonstrated that sensitizers induce a relevant up-regulation of activation markers such as CD86, CD54, IL-8 or IL-1{beta} in human myeloid cell lines (e.g., U937, MUTZ-3, THP-1) or in human peripheral blood monocyte-derived dendritic cells (PBMDCs). The present study aimed at the identification of new dendritic cell activation markers in order to further improve the in vitro evaluation ofmore » the sensitizing potential of chemicals. We have compared the gene expression profiles of PBMDCs and the human cell line MUTZ-3 after a 24-h exposure to the moderate sensitizer cinnamaldehyde. A list of 80 genes modulated in both cell types was obtained and a set of candidate marker genes was selected for further analysis. Cells were exposed to selected sensitizers and non-sensitizers for 24 h and gene expression was analyzed by quantitative real-time reverse transcriptase-polymerase chain reaction. Results indicated that PIR, TRIM16 and two Nrf2-regulated genes, CES1 and NQO1, are modulated by most sensitizers. Up-regulation of these genes could also be observed in our recently published DC-activation test with U937 cells. Due to their role in DC activation, these new genes may help to further refine the in vitro approaches for the screening of the sensitizing properties of a chemical.« less

KPT-330 inhibitor of CRM1 (XPO1)-mediated nuclear export has selective anti-leukaemic activity in preclinical models of T-cell acute lymphoblastic leukaemia and acute myeloid leukaemia.

PubMed

Etchin, Julia; Sanda, Takaomi; Mansour, Marc R; Kentsis, Alex; Montero, Joan; Le, Bonnie T; Christie, Amanda L; McCauley, Dilara; Rodig, Scott J; Kauffman, Michael; Shacham, Sharon; Stone, Richard; Letai, Anthony; Kung, Andrew L; Thomas Look, A

2013-04-01

This study explored the anti-leukaemic efficacy of novel irreversible inhibitors of the major nuclear export receptor, chromosome region maintenance 1 (CRM1, also termed XPO1). We found that these novel CRM1 antagonists, termed SINE (Selective Inhibitors of Nuclear Export), induced rapid apoptosis at low nanomolar concentrations in a panel of 14 human T-cell acute lymphoblastic leukaemia (T-ALL) cell lines representing different molecular subtypes of the disease. To assess in vivo anti-leukaemia cell activity, we engrafted immunodeficient mice intravenously with the human T-ALL MOLT-4 cells, which harbour activating mutations of NOTCH1 and NRAS as well as loss of function of the CDKN2A, PTEN and TP53 tumour suppressors and express a high level of oncogenic transcription factor TAL1. Importantly, we examined the in vivo anti-leukaemic efficacy of the clinical SINE compound KPT-330 against T-ALL and acute myeloid leukaemia (AML) cells. These studies demonstrated striking in vivo activity of KPT-330 against T-ALL and AML cells, with little toxicity to normal murine haematopoietic cells. Taken together, our results show that SINE CRM1 antagonists represent promising 'first-in-class' drugs with a novel mechanism of action and wide therapeutic index, and imply that drugs of this class show promise for the targeted therapy of T-ALL and AML. © 2013 Blackwell Publishing Ltd.

Fv1-like restriction of N-tropic replication-competent murine leukaemia viruses in mCAT-1-expressing human cells.

PubMed

Aagaard, Lars; Mikkelsen, Jacob Giehm; Warming, Søren; Duch, Mogens; Pedersen, Finn Skou

2002-02-01

To study the replication of murine leukaemia viruses in human cells we have used full-length as well as EGFP-tagged ecotropic viruses in combination with mCAT-1-expressing human cells. We present results showing that N-tropic murine leukaemia viruses are restricted in both infection and replication in such cells while B-tropic viruses, modified at capsid position 110, escape restriction. These results support a recently reported Fv1-like restriction in mammalian cells. We extend the analysis of Fv1-like restriction by demonstrating that NB-tropic viruses also escape restriction and human mCAT-1-expressing cells are thus similar to murine Fv1(b) cells with respect to infection though the ecotropic receptor pathway.

Carnitine prevents the early mitochondrial damage induced by methylglyoxal bis(guanylhydrazone) in L1210 leukaemia cells.

PubMed Central

Nikula, P; Ruohola, H; Alhonen-Hongisto, L; Jänne, J

1985-01-01

We previously found that the anti-cancer drug methylglyoxal bis(guanylhydrazone) (mitoguazone) depresses carnitine-dependent oxidation of long-chain fatty acids in cultured mouse leukaemia cells [Nikula, Alhonen-Hongisto, Seppänen & Jänne (1984) Biochem. Biophys. Res. Commun. 120, 9-14]. We have now investigated whether carnitine also influences the development of the well-known mitochondrial damage produced by the drug in L1210 leukaemia cells. Palmitate oxidation was distinctly inhibited in tumour cells exposed to 5 microM-methylglyoxal bis(guanylhydrazone) for only 7 h. Electron-microscopic examination of the drug-exposed cells revealed that more than half of the mitochondria were severely damaged. Similar exposure of the leukaemia cells to the drug in the presence of carnitine not only abolished the inhibition of fatty acid oxidation but almost completely prevented the drug-induced mitochondrial damage. The protection provided by carnitine appeared to depend on the intracellular concentration of methylglyoxal bis(guanylhydrazone), since the mitochondria-sparing effect disappeared at higher drug concentrations. Images Fig. 1. PMID:3837667

Cell markers in the recognition of acute myeloblastic leukaemia subtypes.

PubMed

Andoljsek, Dusan; Preloznik Zupan, Irena; Zontar, Darja; Cernelc, Peter; Mlakar, Uros; Modic, Mojca; Pretnar, Joze; Zver, Samo

2002-01-01

The diagnosis of acute myeloblastic leukaemia (AML) is based on cell morphology, cytogenetic and molecular changes, cell markers and clinical data. Our aim was to establish whether morphology and cell markers are comparable in the evaluation of AML. Bone marrow smears were analysed, and flow cytometry and monoclonal antibodies were used to determine cell type and maturity. Morphology and cell markers correlated differently in different AML subtypes.

Epigenetic synergies between biotin and folate in the regulation of pro-inflammatory cytokines and repeats

PubMed Central

Xue, Jing; Zempleni, Janos

2013-01-01

The protein biotin ligase, holocarboxylase synthetase (HLCS), is a chromatin protein that interacts physically with the DNA methyltransferase DNMT1, the methylated cytosine binding protein MeCP2, and the histone H3 K9-methyltransferase EHMT1, all of which participate in folate-dependent gene repression. Here we tested the hypothesis that biotin and folate synergize in the repression of pro-inflammatory cytokines and long-terminal repeats (LTRs), mediated by interactions between HLCS and other chromatin proteins. Biotin and folate supplementation could compensate for each other’s deficiency in the repression of LTRs in Jurkat and U937 cells. For example, when biotin-deficient Jurkat cells were supplemented with folate, the expression of LTRs decreased by >70%. Epigenetic synergies were more complex in the regulation of cytokines compared with LTRs. For example, the abundance of TNF-α was 100% greater in folate- and biotin-supplemented U937 cells compared with biotin-deficient and folate-supplemented cells. The NF-κB inhibitor curcumin abrogated the effects of folate and biotin in cytokine regulation, suggesting that transcription factor signaling adds an extra layer of complexity to the regulation of cytokine genes by epigenetic phenomena. We conclude that biotin and folate synergize in the repression of LTRs and that these interactions are probably mediated by HLCS-dependent epigenetic mechanisms. In contrast, synergies between biotin and folate in the regulation of cytokines need to be interpreted in the context of transcription factor signaling. PMID:24007195

CD36 signaling inhibits the translation of heat shock protein 70 induced by oxidized low density lipoprotein through activation of peroxisome proliferators-activated receptor γ

PubMed Central

Lee, Kyoung-Jin; Ha, Eun-Soo; Kim, Min-Kyoung; Lee, Sang-Hoon; Suh, Jae Sung; Lee, Sun-Hee; Park, Kyeong Han; Park, Jeong Hyun; Kim, Dae Joong; Kang, Dongmin; Kim, Byung-Chul; Jeoung, Dooil; Kim, Young-Kyoun; Kim, Ho-Dirk

2008-01-01

Oxidized LDL (OxLDL), a causal factor in atherosclerosis, induces the expression of heat shock proteins (Hsp) in a variety of cells. In this study, we investigated the role of CD36, an OxLDL receptor, and peroxisome proliferator-activated receptor γ (PPARγ) in OxLDL-induced Hsp70 expression. Overexpression of dominant-negative forms of CD36 or knockdown of CD36 by siRNA transfection increased OxLDL-induced Hsp70 protein expression in human monocytic U937 cells, suggesting that CD36 signaling inhibits Hsp70 expression. Similar results were obtained by the inhibition of PPARγ activity or knockdown of PPARγ expression. In contrast, overexpression of CD36, which is induced by treatment of MCF-7 cells with troglitazone, decreased Hsp70 protein expression induced by OxLDL. Interestingly, activation of PPARγ through a synthetic ligand, ciglitazone or troglitazone, decreased the expression levels of Hsp70 protein in OxLDL-treated U937 cells. However, major changes in Hsp70 mRNA levels were not observed. Cycloheximide studies demonstrate that troglitazone attenuates Hsp70 translation but not Hsp70 protein stability. PPARγ siRNA transfection reversed the inhibitory effects of troglitazone on Hsp70 translation. These results suggest that CD36 signaling may inhibit stress-induced gene expression by suppressing translation via activation of PPARγ in monocytes. These findings reveal a new molecular basis for the anti-inflammatory effects of PPARγ. PMID:19116451

Dysregulation of haematopoietic stem cell regulatory programs in acute myeloid leukaemia.

PubMed

Basilico, Silvia; Göttgens, Berthold

2017-07-01

Haematopoietic stem cells (HSC) are situated at the apex of the haematopoietic differentiation hierarchy, ensuring the life-long supply of mature haematopoietic cells and forming a reservoir to replenish the haematopoietic system in case of emergency such as acute blood loss. To maintain a balanced production of all mature lineages and at the same time secure a stem cell reservoir, intricate regulatory programs have evolved to control multi-lineage differentiation and self-renewal in haematopoietic stem and progenitor cells (HSPCs). Leukaemogenic mutations commonly disrupt these regulatory programs causing a block in differentiation with simultaneous enhancement of proliferation. Here, we briefly summarize key aspects of HSPC regulatory programs, and then focus on their disruption by leukaemogenic fusion genes containing the mixed lineage leukaemia (MLL) gene. Using MLL as an example, we explore important questions of wider significance that are still under debate, including the importance of cell of origin, to what extent leukaemia oncogenes impose specific regulatory programs and the relevance of leukaemia stem cells for disease development and prognosis. Finally, we suggest that disruption of stem cell regulatory programs is likely to play an important role in many other pathologies including ageing-associated regenerative failure.

Extended diagnostic criteria for plasmacytoid dendritic cell leukaemia.

PubMed

Garnache-Ottou, Francine; Feuillard, Jean; Ferrand, Christophe; Biichle, Sabeha; Trimoreau, Franck; Seilles, Estelle; Salaun, Véronique; Garand, Richard; Lepelley, Pascale; Maynadié, Marc; Kuhlein, Emilienne; Deconinck, Eric; Daliphard, Sylvie; Chaperot, Laurence; Beseggio, Lucille; Foisseaud, Vincent; Macintyre, Elizabeth; Bene, Marie-Christine; Saas, Philippe; Jacob, Marie-Christine

2009-06-01

The diagnosis of plasmacytoid dendritic cell leukaemia (pDCL) is based on the immunophenotypic profile: CD4(+) CD56(+) lineage(neg) CD45RA(+)/RO(neg) CD11c(neg) CD116(low) CD123(+) CD34(neg) CD36(+) HLA-DR(+). Several studies have reported pDCL cases that do not express this exact profile or expressing some lineage antigens that could thus be misdiagnosed. This study aimed to validate pDCL-specific markers for diagnosis by flow-cytometry or quantitative reverse transcription polymerase chain reaction on bone marrow samples. Expression of markers previously found in normal pDC was analysed in 16 pDCL, four pDCL presenting an atypical phenotype (apDCL) and 113 non-pDC - lymphoid or myeloid - acute leukaemia. CD123 was expressed at significantly higher levels in pDCL and apDCL. BDCA-2 was expressed on 12/16 pDCL and on 2/4 apDCL, but was never detected in the 113 non-pDC acute leukaemia cases. BDCA-4 expression was found on 13/16 pDCL, but also in 12% of non-pDC acute leukaemia. High levels of LILRA4 and TCL1A transcripts distinguished pDCL and apDCL from all other acute leukaemia (except B-cell acute lymphoblastic leukaemia for TCL1A). We thus propose a diagnosis strategy, scoring first the CD4(+) CD56(+/-) MPO(neg) cCD3(neg) cCD79a(neg) CD11c(neg) profile and then the CD123(high), BDCA-2 and BDCA-4 expression. Atypical pDCL can be also identified this way and non-pDC acute leukaemia excluded: this scoring strategy is useful for diagnosing pDCL and apDCL.

Enzyme and membrane markers in leukaemia: recent developments.

PubMed Central

Hoffbrand, A V; Janossy, G

1981-01-01

Terminal deoxynucleotidyl transferase (TdT) assay has proved a valuable test for distinguishing lymphoblastic from myeloblastic leukaemias, particularly in adults whose blast cells are often negative for the c-ALL antigen. The immunofluorescence assay, particularly when used in combination with antisera to surface membrane antigens, has proved a sensitive technique for detecting small numbers of lymphoblasts in extramedullary sites, for example, testis or cerebrospinal fluid, or of residual Thy-ALL blasts in the marrow, which might otherwise be difficult to recognise. Differences in concentration of several enzymes concerned in purine metabolism have been detected between the blast cells in the various acute leukaemias. Adenosine deaminase (ADA) concentrations tend to be higher in Thy-ALL than in other forms of leukaemia, but the wide overlap reduces the diagnostic value of this assay. Thy-ALL blasts, however, appear to be selectively and exquisitely susceptible to inhibition of ADA by the drug deoxycoformycin, which has now been used sucessfully in a number of other wise resistant patients with Thy-ALL to obtain a complete remission. The recently introduced technique for the production of monoclonal antibodies has substantially widened the reagents available for analysing the membrane characteristics of bone marrow stem cells and of cell lineages derived from them. These have revealed previously unsuspected heterogeneity among different cases of acute lymphoblastic leukaemia, for example, among Thy-ALL blasts from different patients, and they have also delineated minor populations of immature thymocytes from which these leukaemic cells are derived. The potential use of these antibodies to prevent graft-versus-host disease by selective removal of T-lymphocytes from donor bone marrow before allogeneic bone marrow transplantation, or to prevent recurrence of Thy-ALL and other lymphoblastic leukaemias or lymphomas by selective removal of leukaemic or lymphoma malignant cells before autologous transplantation, is reviewed. Images Fig. 2 PMID:6785321

Cardiolipin plays a role in KCN-induced necrosis.

PubMed

Tsesin, Natalia; Khalfin, Boris; Nathan, Ilana; Parola, Abraham H

2014-10-01

Cardiolipin (CL) is a unique anionic, dimeric phospholipid found almost exclusively in the inner mitochondrial membrane and is essential for the function of numerous enzymes that are involved in mitochondrial energy metabolism. While the role of cardiolipin in apoptosis is well established, its involvement in necrosis is enigmatic. In the present study, KCN-induced necrosis in U937 cells was used as an experimental model to assess the role of CL in necrosis. KCN addition to U937 cells induced reactive oxygen species (ROS) formation, while the antioxidants inhibited necrosis, indicating that ROS play a role in KCN-induced cell death. Further, CL oxidation was confirmed by the monomer green fluorescence of 10-N-nonyl acridine orange (NAO) and by TLC. Utilizing the red fluorescence of the dimeric NAO, redistribution of CL in mitochondrial membrane during necrosis was revealed. We also showed that the catalytic activity of purified adenosine triphosphate (ATP) synthase complex, known to be modulated by cardiolipin, decreased following KCN treatment. All these events occurred at an early phase of the necrotic process prior to rupture of the cell membrane. Furthermore, CL-deficient HeLa cells were found to be resistant to KCN-induced necrosis as compared with the wild type cells. We suggest that KCN, an effective reversible inhibitor of cytochrome oxidase and thereby of the respiratory chain leads to ROS increase, which in turn oxidizes CL (amongst other membrane phospholipids) and leads to mitochondrial membrane lipid reorganization and loss of CL symmetry. Finally, the resistance of CL-deficient cells to necrosis further supports the notion that CL, which undergoes oxidation during necrotic cell death, is an integral part of the milieu of events taking place in mitochondria leading to membrane disorganization and mitochondrial dysfunction. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Antiproliferative and proapoptotic effects of topotecan in combination with thymoquinone on acute myelogenous leukemia.

PubMed

Khalife, Rana; El-Hayek, Stephany; Stephany, El-Hayek; Tarras, Omayr; Hodroj, Mohammad Hassan; Rizk, Sandra

2014-09-01

Topotecan has shown promising antineoplastic activity in solid tumors and acute leukemia. Because of the primary dose-limiting toxicity of topotecan, it is necessary to identify other agents that can work synergistically with topotecan, potentially increasing its efficacy while limiting its toxicity. Many studies showed synergism in combination of topotecan with gemcitabine and bortezomib. Other studies report the increase in growth inhibition of gemcitabine or oxaliplatin when cells were preexposed to naturally occurring drugs such as thymoquinone. The aim of this project was to study the mode of action of topotecan along with thymoquinone, on survival and apoptosis pathways in acute myelogenous leukemia (AML) cell lines, and to investigate the potential synergistic effect of thymoquinone on topotecan. U937 cells were incubated with different topotecan and thymoquinone concentrations for 24 and 48 hours, separately and in combination. Cell proliferation was determined using WST-1 (Roche) reagent. The effect of the compounds on protein expression of Bax, Bcl2, p53, caspase-9, -8, and -3 was determined using Western blot analysis. Cell cycle analysis was performed in addition to annexin/propidium iodide staining. Thymoquinone and topotecan exhibited antiproliferative effects on U937 cells when applied separately. In combination, the reduction in proliferation was extremely significant with a major increase in the expression levels of Bax/Bcl2, p53, and caspase-3 and -9. Preexposure with thymoquinone resulted in an increase in cell growth inhibition compared with topotecan treatment. Thymoquinone, when combined with topotecan in noncytotoxic doses, produced synergistic antiproliferative and proapoptotic effects in AML cells. Preexposure to thymoquinone seems to be more effective than simultaneous application with topotecan. Copyright © 2014 Elsevier Inc. All rights reserved.

The Culture-Repopulating Ability Assays and Incubation in Low Oxygen: A Simple Way to Test Drugs on Leukaemia Stem or Progenitor Cells

PubMed Central

Cipolleschi, Maria Grazia; Rovida, Elisabetta; Sbarba, Persio Dello

2013-01-01

The Culture-Repopulating Ability (CRA) assays is a method to measure in vitro the bone marrow-repopulating potential of haematopoietic cells. The method was developed in our laboratory in the course of studies based on the use of growth factor-supplemented liquid cultures to study haematopoietic stem/progenitor cell resistance to, and selection at, low oxygen tensions in the incubation atmosphere. These studies led us to put forward the first hypothesis of the existence in vivo of haematopoietic stem cell niches where oxygen tension is physiologically lower than in other bone marrow areas. The CRA assays and incubation in low oxygen were later adapted to the study of leukaemias. Stabilized leukaemia cell lines, ensuring genetically homogeneous cells and enhancing repeatability of results, were found nevertheless phenotypically heterogeneous, comprising cell subsets exhibiting functional phenotypes of stem or progenitor cells. These subsets can be assayed separately, provided an experimental system capable to select one from another (such as different criteria for incubation in low oxygen) is established. On this basis, a two-step procedure was designed, including a primary culture of leukaemia cells in low oxygen for different times, where drug treatment is applied, followed by the transfer of residual cell population (CRA assay) to a drug-free secondary culture incubated at standard oxygen tension, where the expansion of population is allowed. The CRA assays, applied to cell lines first and then to primary cells, represent a simple and relatively rapid, yet accurate and reliable, method for the pre-screening of drugs potentially active on leukaemias which in our opinion could be adopted systematically before they are tested in vivo. PMID:23394087

Acute B cell lymphoblastic leukaemia in a 12-week-old greyhound.

PubMed

Adams, J; Mellanby, R J; Villiers, E; Baines, S; Woodger, N

2004-11-01

A 12-week-old greyhound had a two-day history of lethargy, inappetence and shifting lameness. Clinical examination revealed pyrexia and hepatosplenomegaly. Haematological examination showed anaemia, thrombocytopenla, neutropenla and large numbers of atypical mononuclear leucocytes. A diagnosis of acute B cell lymphoblastic leukaemia was made following flow cytometric immunophenotyping of the leucocytes. The owner declined further evaluation and the dog was treated symptomatically with antibiotics. After a brief improvement, the dog's condition deteriorated and it was euthanased four days after initial presentation. The case was unusual because acute lymphoid leukaemia in the dog is most frequently reported in mature animals. This is in contrast to humans, where acute leukaemia is one of the most common childhood cancers.

Inhibition of EGR-1 and NF-kappa B gene expression by dexamethasone during phorbol ester-induced human monocytic differentiation.

PubMed

Hass, R; Brach, M; Gunji, H; Kharbanda, S; Kufe, D

1992-10-20

The treatment of human myeloid leukemia cells (HL-60, U-937, THP-1) with 12-O-tetradecanoylphorbol-13-acetate (TPA) is associated with growth arrest and appearance of a differentiated monocytic phenotype. While previous studies have reported that the glucocorticoid dexamethasone blocks phenotypic characteristics of monocytic differentiation, we demonstrated in the present work that dexamethasone delays the effects of TPA on the loss of U-937 cell proliferation. We also demonstrated that this glucocorticoid inhibits TPA-induced increases in expression of the EGR-1 early response gene. The results of nuclear run-on assays and half-life experiments indicated that this effect of dexamethasone is regulated at the post-transcriptional level. Similar studies were performed for the NF-kappa B gene. While TPA treatment was associated with transient increases in NF-kappa B mRNA levels, this induction was blocked by dexamethasone. In contrast, dexamethasone had no significant effect on the activation of pre-existing NF-kappa B protein as determined in DNA-binding assays. Taken together, these findings suggest that the activated glucocorticoid receptor inhibits signaling pathways which include expression of the EGR-1 and NF-kappa B genes and that such effects may contribute to a block in TPA-induced monocytic differentiation.

Prolymphocytic leukaemia: surface morphology in 21 cases as seen by scanning electron microscopy and comparison with B-type CLL and CLL in 'prolymphocytoid' transformation.

PubMed

Polliack, A; Leizerowitz, R; Berrebi, A; Gamliel, H; Galili, N; Gurfel, D; Catovsky, D

1984-08-01

The surface architecture of leukaemic cells obtained from 21 cases of proven prolymphocytic leukaemia (PLL) and eight cases of chronic lymphocytic leukaemia (CLL) with 'prolymphocytoid' transformation (PL-CLL) was compared with the cell surface morphology of leukaemic cells obtained from 46 cases of B-type CLL, using the scanning electron microscope (SEM). All cases were defined by cytochemistry, immunological markers and transmission electron microscopy prior to SEM examination. B-CLL cells showed the well-recognized spectrum of surface architecture described in earlier studies. The majority of cells had moderate numbers of short microvilli, although in a minority, cells with relatively smooth surfaces predominated. In seven of the eight cases of PL-CLL, cells were villous in nature and in this respect similar to CLL cells; however, more cells with dense microvilli were seen. The prolymphocytic cells were recognized by their larger size and in 18 of the 19 cases of B-derived PLL, villous cells predominated. Two cases of T-derived PLL showed variable cell surface morphology ranging from smooth to moderately villous. It appears that B-PLL cells are most frequently villous and display more surface microvilli than B-CLL cells. B-prolymphocytes display the surface features regarded as characteristic for neoplastic B-cells as seen in patients with B-type lymphoma and leukaemia.

Costimulatory molecule expression following exposure to orthopaedic implants wear debris.

PubMed

Bainbridge, J A; Revell, P A; Al-Saffar, N

2001-03-05

Patients with long-term orthopedic implants may develop inflammatory reactions due to the accumulation of biomaterial particles both around the implant and in distant organs. The exact impact of these particles on the normal immune cell function still remain relatively unclear. Activation of T-cells following exposure to biomaterial particles is driven by macrophages and requires synergistic signals primed by both antigen presentation and costimulation. The pattern of costimulatory molecule expression (CD80,CD86) was primarily examined using immunohistochemistry on tissue specimens of bone/implant interface membranes taken from sites of bone erosion. Additionally, costimulatory molecule expression was also assessed in the monocytic leukemia cell line U937 following exposure to clinically relevant titanium aluminum vanadium (TiAlV) and stainless steel particles (FeCrNi) cultured in vitro. This study demonstrates the induction and prominent expression of CD86 on almost all macrophage subsets at the bone/implant interface, including fused forms and large multinucleated giant cells (MNGC). In vitro analysis also indicated phagocytosis of metal particles by differentiated U937 caused significant induction of both CD80 and CD86 (p < 0.01), although the expression of CD86 dominated following prolonged exposure. The data presented highlights that CD86 is the predominant costimulatory molecule ligating to the complementary CD28 molecule at the inflammatory lesion of the interface. We propose that the intracellular presence of indigestible implant material, in addition to elevated costimulatory molecule expression, may promote T-cell inflammatory reactions at sites close to and distant from the orthopedic implant.

Hyperglycemic Conditions Prime Cells for RIP1-dependent Necroptosis.

PubMed

LaRocca, Timothy J; Sosunov, Sergey A; Shakerley, Nicole L; Ten, Vadim S; Ratner, Adam J

2016-06-24

Necroptosis is a RIP1-dependent programmed cell death (PCD) pathway that is distinct from apoptosis. Downstream effector pathways of necroptosis include formation of advanced glycation end products (AGEs) and reactive oxygen species (ROS), both of which depend on glycolysis. This suggests that increased cellular glucose may prime necroptosis. Here we show that exposure to hyperglycemic levels of glucose enhances necroptosis in primary red blood cells (RBCs), Jurkat T cells, and U937 monocytes. Pharmacologic or siRNA inhibition of RIP1 prevented the enhanced death, confirming it as RIP1-dependent necroptosis. Hyperglycemic enhancement of necroptosis depends upon glycolysis with AGEs and ROS playing a role. Total levels of RIP1, RIP3, and mixed lineage kinase domain-like (MLKL) proteins were increased following treatment with high levels of glucose in Jurkat and U937 cells and was not due to transcriptional regulation. The observed increase in RIP1, RIP3, and MLKL protein levels suggests a potential positive feedback mechanism in nucleated cell types. Enhanced PCD due to hyperglycemia was specific to necroptosis as extrinsic apoptosis was inhibited by exposure to high levels of glucose. Hyperglycemia resulted in increased infarct size in a mouse model of brain hypoxia-ischemia injury. The increased infarct size was prevented by treatment with nec-1s, strongly suggesting that increased necroptosis accounts for exacerbation of this injury in conditions of hyperglycemia. This work reveals that hyperglycemia represents a condition in which cells are extraordinarily susceptible to necroptosis, that local glucose levels alter the balance of PCD pathways, and that clinically relevant outcomes may depend on glucose-mediated effects on PCD. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Agglutination reactions of human leucocytes

PubMed Central

Schulz, Jeanette; Muller, Helga

1963-01-01

Agglutination tests with various sera and leucocytes from 58 leukaemic patients and 61 patients without leukaemia are reported. The agglutination of white blood cells by guinea-pig serum is of limited value in the diagnosis of leukaemia, though the test may be helpful in distinguishing leukaemia from other lymphomatous disorders. Leuco-autoagglutinins were demonstrated more frequently than expected. Eleven leukaemic and six non-leukaemic sera agglutinated autologous leucocytes. White blood cell agglutinins showed no apparent relationship to maturity or numbers of circulating leucocytes or to previous blood transfusions, x-irradiation, or therapy with antimetabolites. PMID:14044034

Induction of osteosarcoma and acute myeloid leukaemia in CBA/H mice by the alpha-emitting nuclides, uranium-233, plutonium-239 and amercium-241.

PubMed

Ellender, M; Harrison, J D; Pottinger, H; Thomas, J M

2001-01-01

To compare tumour induction in CBA/H mice, principally osteosarcoma and acute myeloid leukaemia, resulting from exposure to the alpha-emitting nuclides, uranium-233, plutonium-239 and americium-241, and to relate differences between the three nuclides to the pattern of dose delivery within tissues. Each nuclide was administered intraperitoneally in citrate solution to three groups of adult male CBA/H mice at levels of activity which gave estimated life-time average skeletal doses of about 0.25-0.3 Gy, 0.5-1 Gy and 1-2 Gy. Animals were carefully monitored and sacrificed as soon as they showed signs of ill health; tumours were identified by standard histopathological techniques. Statistical modelling by Cox regression showed that, considering all three nuclides together, there was a highly significant increase in risk of death from osteosarcoma or myeloid leukaemia with increasing dose rate. For osteosarcoma, the effect was significantly greater for 239Pu than 241Am, while separate analysis for 233U showed no significant increase with increasing dose rate. For example, the increase in relative risk of death from osteosarcoma for an increase in life-time average dose rate to bone of 1 mGyd(-1) was 4.2 (2.7-6.5) for 239Pu, 2.3 (1.4-3.4) for 241Am and 1.1 (0.4-3.1) for 233U. For myeloid leukaemia, there was no significant difference between 239Pu and 241Am in the effect of dose rate. The increase in relative risk from myeloid leukaemia for an increase in average dose rate of 1 mGyd(-1) was 1.8 (1.1-2.8) for 239Pu, 2.0 (1.4-2.9) for 241Am and 1.5 (0.8-2.7) for 233U. Significant increases in renal and hepatic carcinomas were also recorded in animals exposed to 233U and 241Am, respectively. Studies of the distribution of the nuclides within the skeleton, published separately, have shown differences in their retention in individual bones and within bone. The proportions of decays occurring near to endosteal bone surfaces and throughout bone marrow were in the order: 239Pu> 241Am>233U. For osteosarcoma, the relative effectiveness of the nuclides in terms of average bone dose, in the order 239Pu>241Am>233U, is consistent with the proportion of dose delivered near to endosteal surfaces. For myeloid leukaemia, the greater effectiveness of 239Pu and 241Am than 233U is consistent with their accumulation in marrow.

Leukemia-associated gene MLAA-34 reduces arsenic trioxide-induced apoptosis in HeLa cells via activation of the Wnt/β-catenin signaling pathway.

PubMed

Zhang, Pengyu; Zhao, Xuan; Zhang, Wenjuan; He, Aili; Lei, Bo; Zhang, Wanggang; Chen, Yinxia

2017-01-01

Our laboratory previously used the SEREX method in U937 cells and identified a novel leukemia-associated gene MLAA-34, a novel splice variant of CAB39L associated with acute monocytic leukemia, that exhibited anti-apoptotic activities in U937 cells. Whether MLAA-34 has an anti-apoptotic role in other tumor cells has not yet been reported. We explored whether MLAA-34 exhibited anti-apoptotic effects in HeLa cervical cancer cells and the possible mechanism of action. We generated a HeLa cell line stably expressing MLAA-34 and found that MLAA-34 overexpression had no effect on the growth, apoptosis and cell cycle of HeLa cells. However, upon treatment with arsenic trioxide (ATO) to induce apoptosis, the cell viability and colony formation ability of ATO-treated MLAA-34 stable HeLa cells were significantly higher than that of ATO-treated controls, and the apoptosis rate and proportion of G2/M cells also decreased. We found that ATO treatment of HeLa cells resulted in significant decreases in the expression of β-catenin mRNA and protein and the downstream target factors c-Myc, cyclin B1, and cyclin D1 in the Wnt signaling pathway. Notably, ATO-treated MLAA-34 stable HeLa cells showed a significant reduction in the ATO-mediated downregulation of these factors. In addition, MLAA-34 overexpression significantly increased the expression of nuclear β-catenin protein in ATO-treated cells compared with HeLa cells treated only with ATO. Thus, here we have found that the Wnt/β-catenin signaling pathway is involved in ATO-induced apoptosis in HeLa cells. MLAA-34 reduces ATO-induced apoptosis and G2/M arrest, and the anti-apoptotic effect may be achieved by activating the Wnt/β-catenin signaling pathway in HeLa cells.

Leukemia-associated gene MLAA-34 reduces arsenic trioxide-induced apoptosis in HeLa cells via activation of the Wnt/β-catenin signaling pathway

PubMed Central

Zhao, Xuan; Zhang, Wenjuan; He, Aili; Lei, Bo; Zhang, Wanggang; Chen, Yinxia

2017-01-01

Our laboratory previously used the SEREX method in U937 cells and identified a novel leukemia-associated gene MLAA-34, a novel splice variant of CAB39L associated with acute monocytic leukemia, that exhibited anti-apoptotic activities in U937 cells. Whether MLAA-34 has an anti-apoptotic role in other tumor cells has not yet been reported. We explored whether MLAA-34 exhibited anti-apoptotic effects in HeLa cervical cancer cells and the possible mechanism of action. We generated a HeLa cell line stably expressing MLAA-34 and found that MLAA-34 overexpression had no effect on the growth, apoptosis and cell cycle of HeLa cells. However, upon treatment with arsenic trioxide (ATO) to induce apoptosis, the cell viability and colony formation ability of ATO-treated MLAA-34 stable HeLa cells were significantly higher than that of ATO-treated controls, and the apoptosis rate and proportion of G2/M cells also decreased. We found that ATO treatment of HeLa cells resulted in significant decreases in the expression of β-catenin mRNA and protein and the downstream target factors c-Myc, cyclin B1, and cyclin D1 in the Wnt signaling pathway. Notably, ATO-treated MLAA-34 stable HeLa cells showed a significant reduction in the ATO-mediated downregulation of these factors. In addition, MLAA-34 overexpression significantly increased the expression of nuclear β-catenin protein in ATO-treated cells compared with HeLa cells treated only with ATO. Thus, here we have found that the Wnt/β-catenin signaling pathway is involved in ATO-induced apoptosis in HeLa cells. MLAA-34 reduces ATO-induced apoptosis and G2/M arrest, and the anti-apoptotic effect may be achieved by activating the Wnt/β-catenin signaling pathway in HeLa cells. PMID:29059232

Detection of different Ikaros isoforms in human leukaemias using real-time quantitative polymerase chain reaction.

PubMed

Olivero, S; Maroc, C; Beillard, E; Gabert, J; Nietfeld, W; Chabannon, C; Tonnelle, C

2000-09-01

The Ikaros gene is an essential regulator in development and haematopoiesis. Dysregulated Ikaros gene expression participates in leukaemic processes, as evidenced in animal models, and by analyses of blast-cell populations from leukaemic patients. We used real-time quantitative polymerase chain reaction (PCR) to evaluate the relative abundance of several Ikaros transcript isoforms in a variety of leukaemic-cell samples. Total RNA was isolated from bone-marrow or blood-cell samples collected at diagnosis in children or adult patients, 18 of whom had acute myeloblastic leukaemia (AML), 61 of whom had acute lymphoblastic leukaemia (ALL) and 11 of whom had chronic myeloid leukaemia (CML). The ratio (Ik1 + Ik2)/(Ik1 + Ik2 + Ik4 + Ik7 + Ik8) ranged from 13.5% to 85% and was lower (P < 0. 05) in samples from patients with m-bcr-abl ALL. An alternative splicing resulting in the deletion of 30 nucleotides at the end of exon 6 was observed in leukaemic samples, and in normal thymus and bone marrow. Our results are consistent with previous reports and suggest that the pattern of expression of the different human Ikaros isoforms are not homogeneous among different subsets of leukaemias.

Quercus Suber L. Cork Extracts Induce Apoptosis in Human Myeloid Leukaemia HL-60 Cells.

PubMed

Bejarano, Ignacio; Godoy-Cancho, Belén; Franco, Lourdes; Martínez-Cañas, Manuel A; Tormo, María A

2015-08-01

Quercus suber L. cork contains a diversity of phenolic compounds, mostly low molecular weight phenols. A rising number of reports support with convergent findings that polyphenols evoke pro-apoptotic events in cancerous cells. However, the literature related to the anti-cancer bioactivity of Q. suber L. cork extractives (QSE) is still limited. Herein, we aim to describe the antitumor potential displayed by cork extractives obtained by different extraction methods in the human promyelocytic leukaemia cells. In order to quantify the effects of QSE on cancer cells viability, phosphatidylserine exposure, caspase-3 activity, mitochondrial membrane potential and cell cycle were evaluated. The results indicated that the QSE present a time-dependent and dose-dependent cytotoxicity in the human promyelocytic leukaemia cells. Such a noxious effect leads these leukaemia cells to their death through apoptotic processes by altering the mitochondrial outer membrane potential, activating caspase-3 and externalizing phosphatidylserine. However, cells cycle progression was not affected by the treatments. This study contributes to open a new way to use this natural resource by exploiting its anti-cancer properties. Moreover, it opens new possibilities of application of cork by-products, being more efficient in the sector of cork-based agriculture. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Deoxycytidine kinase is downregulated under hypoxic conditions and confers resistance against cytarabine in acute myeloid leukaemia.

PubMed

Degwert, Nicole; Latuske, Emily; Vohwinkel, Gabi; Stamm, Hauke; Klokow, Marianne; Bokemeyer, Carsten; Fiedler, Walter; Wellbrock, Jasmin

2016-09-01

Leukaemia initiating cells reside within specialised niches in the bone marrow where they undergo complex interactions with different stromal cell types. The bone marrow niche is characterised by a low oxygen content resulting in high expression of hypoxia-inducible factor 1 α in leukaemic cells conferring a negative prognosis to patients with acute myeloid leukaemia (AML). In the current study, we investigated the impact of hypoxic vs. normoxic conditions on the sensitivity of AML cell lines and primary AML blasts to cytarabine. AML cells cultured under 6% oxygen were significantly more resistant against cytarabine compared to cells cultured under normoxic conditions in proliferation and colony-formation assays. Interestingly upon cultivation under hypoxia, the expression of the cytarabine-activating enzyme deoxycytidine kinase was downregulated in all analysed AML cell lines and primary AML samples representing a possible mechanism for resistance to chemotherapy. Furthermore, the downregulation of deoxycytidine kinase could be associated with hypoxia-inducible factor 1 α as treatment with its inhibitor BAY87-2243 hampered the downregulation of deoxycytidine kinase expression under hypoxic conditions. In conclusion, our data reveal that hypoxia-induced downregulation of deoxycytidine kinase represents one stroma-cell-independent mechanism of drug resistance to cytarabine in acute myeloid leukaemia. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Leukaemia at Queen Elizabeth Central Hospital in Blantyre, Malawi.

PubMed

Mukiibi, J M; Nyirenda, C M; Adewuyi, J O; Mzula, E L; Magombo, E D; Mbvundula, E M

2001-07-01

To determine the patterns of leukaemias seen in Malawians at Queen Elizabeth Central Hospital (QECH) and to compare the findings with those from elsewhere. An overview of the problems encountered in the management of leukaemia in developing countries especially those in sub-Saharan Africa are highlighted. Retrospective descriptive analysis of consecutive leukaemia cases seen from January 1994 through December 1998. Of the 95 leukaemia patients diagnosed during the study period, childhood (0-15 years) leukaemia occurred in 27 (28.4%) patients while adulthood (above 15 years) leukaemia accounted for 68 (71.6%) patients. The main leukaemia types were: acute lymphoblastic leukaemia (ALL) 14 (14.7%), acute myeloblastic leukaemia (AML) 25 (26.3%), chronic myeloid (granulocytic) leukaemia (CML) 32 (33.7%), chronic lymphocytic (lymphatic) leukaemia (CLL) 22 (23.2%) and hairy cell leukaemia (HCL) two (2.1%) patients. Most of the acute leukaemia (AL) cases occurred in the six to 15 year age bracket with a male preponderance. In ALL, lymphadenopathy was the commonest presenting feature followed by pallor (92.9%) while in the AML group, pallor occurred in 80% of cases. Abdominal swelling (87.5%) due to splenomegaly (81.3%) were the main clinical features in the CML group whereas lymphadenopathy (63.6%) followed by splenomegaly (59.1%) were the dominant presenting features in CLL. Haematologically, although leucocytosis characterised both acute and chronic leukaemias, most cases of acute leukaemia presented with more severe anaemia (Hb < 7 g/dl) and marked thrombocytopenia (Platelet count < 50 x 10(9)/l) than the chronic leukaemias. The study shows that leukaemias are not rare in Malawi and cases which were diagnosed in this series probably only represent the tip of the iceberg. While there is need to increase diagnostic awareness among clinicians and laboratory staff, the severe chronic shortage of cytotoxic drugs and lack of supportive care facilities commonly encountered in developing countries should be realistically addressed through cost-sharing, cost recovery, adequate government subvention and donations from charitable organisations.

The role of multiparametric flow cytometry in the detection of minimal residual disease in acute leukaemia.

PubMed

Lee, Denise; Grigoriadis, George; Westerman, David

2015-12-01

Flow cytometry is the most accessible method for minimal residual disease (MRD) detection due to its availability in most haematological centres. Using a precise combination of different antibodies, immunophenotypic detection of MRD in acute leukaemia can be performed by identifying abnormal combinations or expressions of antigens on malignant cells at diagnosis, during and post treatment. These abnormal phenotypes, referred to as leukaemia-associated immunophenotypes (LAIPs) are either absent or expressed at low frequency in normal bone marrow (BM) cells and are used to monitor the behaviour and quantitate the amount of residual disease following treatment. In paediatric acute lymphoblastic leukaemia (ALL), the level of MRD by multiparametric flow cytometry (MPFC) during therapy is recognised as an important predictor of outcome. Although less extensively studied, adult ALL and adult and paediatric acute myeloid leukaemia (AML) have also demonstrated similar findings. The challenge now is incorporating this information for risk-stratification so that therapy can be tailored individually and ultimately improve outcome while also limiting treatment-related toxicity. In this review we will elaborate on the current and future role of MPFC in MRD in acute leukaemia while also addressing its limitations.

Thalidomide inhibits inflammatory and angiogenic activation of human intestinal microvascular endothelial cells (HIMEC).

PubMed

Rafiee, Parvaneh; Stein, Daniel J; Nelson, Victoria M; Otterson, Mary F; Shaker, Reza; Binion, David G

2010-02-01

The glutamic acid derivative thalidomide is a transcriptional inhibitor of TNF-alpha but is also known to affect human blood vessels, which may underlie its teratogenicity. Thalidomide has been used in the treatment of refractory Crohn's disease (CD), but the therapeutic mechanism is not defined. We examined the effect of thalidomide on primary cultures of human intestinal microvascular endothelial cells (HIMEC), the relevant endothelial cell population in inflammatory bowel disease (IBD), to determine its effect on endothelial activation, leukocyte interaction, and VEGF-induced angiogenesis. HIMEC cultures were pretreated with thalidomide before activation with either TNF-alpha/LPS or VEGF. A low-shear-stress flow adhesion assay with either U-937 or whole blood was used to assess HIMEC activation following TNF-alpha/LPS, and a Wright's stain identified adherent leukocytes. Expression of cell adhesion molecules (E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1) was assessed using radioimmunoassay. Effects of thalidomide on NF-kappaB activation, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) expression in TNF-alpha/LPS-activated HIMEC were determined by RT-PCR and Western blotting. Thalidomide blocked adhesion of both U-937 and whole blood leukocytes by 50% in HIMEC, inhibiting binding of all classes of leukocytes. Thalidomide also blocked NF-kappaB and cell adhesion molecule expression in HIMEC. In marked contrast, thalidomide did not affect either iNOS or COX-2 expression, two key molecules that play a role in the downregulation of HIMEC activation. VEGF-induced HIMEC transmigration, growth, proliferation, tube formation, and Akt phosphorylation were significantly inhibited by thalidomide. In summary, thalidomide exerted a potent effect on HIMEC growth and activation, suggesting that it may also function via an endothelial mechanism in the treatment of CD.

Thalidomide inhibits inflammatory and angiogenic activation of human intestinal microvascular endothelial cells (HIMEC)

PubMed Central

Stein, Daniel J.; Nelson, Victoria M.; Otterson, Mary F.; Shaker, Reza; Binion, David G.

2010-01-01

The glutamic acid derivative thalidomide is a transcriptional inhibitor of TNF-α but is also known to affect human blood vessels, which may underlie its teratogenicity. Thalidomide has been used in the treatment of refractory Crohn's disease (CD), but the therapeutic mechanism is not defined. We examined the effect of thalidomide on primary cultures of human intestinal microvascular endothelial cells (HIMEC), the relevant endothelial cell population in inflammatory bowel disease (IBD), to determine its effect on endothelial activation, leukocyte interaction, and VEGF-induced angiogenesis. HIMEC cultures were pretreated with thalidomide before activation with either TNF-α/LPS or VEGF. A low-shear-stress flow adhesion assay with either U-937 or whole blood was used to assess HIMEC activation following TNF-α/LPS, and a Wright's stain identified adherent leukocytes. Expression of cell adhesion molecules (E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1) was assessed using radioimmunoassay. Effects of thalidomide on NF-κB activation, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) expression in TNF-α/LPS-activated HIMEC were determined by RT-PCR and Western blotting. Thalidomide blocked adhesion of both U-937 and whole blood leukocytes by 50% in HIMEC, inhibiting binding of all classes of leukocytes. Thalidomide also blocked NF-κB and cell adhesion molecule expression in HIMEC. In marked contrast, thalidomide did not affect either iNOS or COX-2 expression, two key molecules that play a role in the downregulation of HIMEC activation. VEGF-induced HIMEC transmigration, growth, proliferation, tube formation, and Akt phosphorylation were significantly inhibited by thalidomide. In summary, thalidomide exerted a potent effect on HIMEC growth and activation, suggesting that it may also function via an endothelial mechanism in the treatment of CD. PMID:19926820

The HIV Nef protein modulates cellular and exosomal miRNA profiles in human monocytic cells.

PubMed

Aqil, Madeeha; Naqvi, Afsar Raza; Mallik, Saurav; Bandyopadhyay, Sanghamitra; Maulik, Ujjwal; Jameel, Shahid

2014-01-01

The HIV Nef protein is a multifunctional virulence factor that perturbs intracellular membranes and signalling and is secreted into exosomes. While Nef-containing exosomes have a distinct proteomic profile, no comprehensive analysis of their miRNA cargo has been carried out. Since Nef functions as a viral suppressor of RNA interference and disturbs the distribution of RNA-induced silencing complex proteins between cells and exosomes, we hypothesized that it might also affect the export of miRNAs into exosomes. Exosomes were purified from human monocytic U937 cells that stably expressed HIV-1 Nef. The RNA from cells and exosomes was profiled for 667 miRNAs using a Taqman Low Density Array. Selected miRNAs and their mRNA targets were validated by quantitative RT-PCR. Bioinformatics analyses were used to identify targets and predict pathways. Nef expression affected a significant fraction of miRNAs in U937 cells. Our analysis showed 47 miRNAs to be selectively secreted into Nef exosomes and 2 miRNAs to be selectively retained in Nef-expressing cells. The exosomal miRNAs were predicted to target several cellular genes in inflammatory cytokine and other pathways important for HIV pathogenesis, and an overwhelming majority had targets within the HIV genome. This is the first study to report miRnome analysis of HIV Nef expressing monocytes and exosomes. Our results demonstrate that Nef causes large-scale dysregulation of cellular miRNAs, including their secretion through exosomes. We suggest this to be a novel viral strategy to affect pathogenesis and to limit the effects of RNA interference on viral replication and persistence.

Inhibition of osteoclast differentiation by overexpression of NDRG2 in monocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, Kyeongah; Nam, Sorim; Kim, Bomi

N-Myc downstream-regulated gene 2 (NDRG2), a member of the NDRG family of differentiation-related genes, has been characterized as a regulator of dendritic cell differentiation from monocytes, CD34{sup +} progenitor cells, and myelomonocytic leukemic cells. In this study, we show that NDRG2 overexpression inhibits the differentiation of U937 cells into osteoclasts in response to stimulation with a combination of macrophage colony-stimulating factor (M-CSF) and soluble receptor activator of NF-κB ligand (RANKL). U937 cells stably expressing NDRG2 are unable to differentiate into multinucleated osteoclast-like cells and display reduced tartrate-resistant acid phosphatase (TRAP) activity and resorption pit formation. Furthermore, NDRG2 expression significantly suppressesmore » the expression of genes that are crucial for the proliferation, survival, differentiation, and function of osteoclasts, including c-Fos, Atp6v0d2, RANK, and OSCAR. The activation of ERK1/2 and p38 is also inhibited by NDRG2 expression during osteoclastogenesis, and the inhibition of osteoclastogenesis by NDRG2 correlates with the down-regulation of the expression of the transcription factor PU.1. Taken together, our results suggest that the expression of NDRG2 potentially inhibits osteoclast differentiation and plays a role in modulating the signal transduction pathway responsible for osteoclastogenesis. - Highlights: • The expression of NDRG2 significantly impairs osteoclast differentiation. • PU.1 and p38 MAPK inhibitions by NDRG2 are critical for the inhibition of osteoclastogenesis. • Knockdown of NDRG2 rescues the ability of monocytes to differentiate into osteoclasts. • NDRG2 expression in BM and primary macrophages also impairs osteoclast differentiation. • This study implies the potential of NDRG2 expression in the inhibition of osteoclastogenesis.« less

Downregulation of Programmed Cell Death 4 by Inflammatory Conditions Contributes to the Generation of the Tumor Promoting Microenvironment

PubMed Central

Yasuda, Michiko; Schmid, Tobias; Rübsamen, Daniela; Colburn, Nancy H.; Irie, Kazuhiro; Murakami, Akira

2012-01-01

Ample evidence has shown key roles of inflammation in tumor promotion and carcinogenesis, and tumor-associated macrophages are known to promote tumor growth and dissemination. Programmed cell death 4 (Pdcd4) is a novel tumor suppressor, and although various studies have revealed that the functions and expression mechanisms of Pdcd4 in tumor promotion, those in regard to inflammation remain unclear. In the present study, we examined whether inflammatory stimuli regulate Pdcd4 expression. 12-O-tetradecanoylphorbol 13-acetate (TPA) suppressed expression of pdcd4 mRNA in human monocytic cell lines (U937, THP-1). Similarly, the bacterial endotoxin lipopolysaccharide (LPS) downregulated pdcd4 level in mouse RAW264.7 and peritoneal macrophages. Furthermore, conditioned medium from LPS-stimulated RAW264.7 macrophages suppressed pdcd4 mRNA in RAW264.7 macrophages, and findings obtained with recombinant tumor necrosis factor-α (TNF-α) and TNF-α-specific siRNA suggested that TNF-α partly mediates LPS-triggered Pdcd4 downregulation via an autocrine mechanism. Specific inhibitors of phosphoinositide-3-kinase (PI3K) and c-jun N-terminus kinase (JNK) restored LPS-abolished pdcd4 mRNA. Consistently, in MCF7 mammary carcinoma cells, conditioned medium from TPA-differentiated/activated U937 cells suppressed pdcd4 mRNA. Additionally, knockdown of pdcd4 in RAW264.7 macrophages using siRNA significantly enhanced LPS-induced TNF-α protein production, and interferon-γ, CC chemokine ligand (Ccl) 1, Ccl20, and interleukin-10 mRNA expression. These results suggest that Pdcd4 suppresses the induction of these inflammatory mediators. Taken together, loss of Pdcd4 in macrophages may be a critical step in establishing the inflammatory environment while that in tumor cells contributes to tumor progression. PMID:20607724

Methylenetetrahydrofolate reductase C677T genetic polymorphisms and risk of leukaemia among the North Indian population.

PubMed

Hussain, Syed Rizwan; Naqvi, Hena; Raza, Syed Tasleem; Ahmed, Faisal; Babu, Sunil G; Kumar, Ashutosh; Zaidi, Zeashan Haider; Mahdi, Farzana

2012-08-01

Leukaemia is a heterogeneous disease in which haematopoietic progenitor cells acquire genetic lesions that lead to a block in differentiation, increased self-renewal, and unregulated proliferation. The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), involved in folate metabolism, plays a crucial role in cells because folate availability is important for DNA integrity. The aim of this case-control study was to evaluate the association of the C677T MTHFR gene polymorphism with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL), chronic myeloid leukaemia (CML) and chronic lymphocytic leukaemia (CLL). A total of 275 leukaemia cases - including AML (n = 112), ALL (n = 81), CML (n = 43), CLL (n = 39) - and 251 age/sex-matched healthy control individuals participated in this study. MTHFR C677T polymorphisms in the cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The average MTHFR 677CC, 677CT, 677TT genotype frequencies of total leukaemia cases were 68.73%, 19.64%, and 11.64% in cases, and 71.71%, 24.30%, and 3.98% in healthy controls, respectively. The average frequency of the MTHFR 677T allele was 21.45% among the cases compared to 16.13% among the controls. In the present case-control study we have observed a higher frequency of the MTHFR 677TT genotype in cases of leukaemia (AML, ALL, CML and CLL) as compared with controls; this might be due to ethnic and geographic variation. As per our findings, although the frequency of the MTHFR 677T allele is moderately high in AML, ALL and CLL, no statistically significant association was found; on the other hand statistically significant association was found in the context of CML cases. Copyright © 2012 Elsevier Ltd. All rights reserved.

Carprofen analogues as sirtuin inhibitors: enzyme and cellular studies.

PubMed

Mellini, Paolo; Carafa, Vincenzo; Di Rienzo, Barbara; Rotili, Dante; De Vita, Daniela; Cirilli, Roberto; Gallinella, Bruno; Provvisiero, Donatella Paola; Di Maro, Salvatore; Novellino, Ettore; Altucci, Lucia; Mai, Antonello

2012-11-01

The best of both: SIRT1/2 inhibitors were developed by combining chemical features of selisistat (SIRT1-selective inhibitor; blue) and carprofen (anti-inflammatory drug; red). The most potent compound (shown) increased acetyl-p53 and acetyl-α-tubulin levels, and induced slight apoptosis at 50 μM in U937 cells, differently from selisistat and carprofen. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The CNGRC-GG-D(KLAKLAK)2 peptide induces a caspase-independent, Ca2+-dependent death in human leukemic myeloid cells by targeting surface aminopeptidase N/CD13

PubMed Central

Bouchet, Sandrine; Tang, Ruoping; Fava, Fanny; Legrand, Ollivier; Bauvois, Brigitte

2016-01-01

The CD13 antigen's binding site for the Asn-Gly-Arg (NGR) motif enables NGR-containing chemotherapeutic drugs to be delivered to CD13-positive tumours. Human CD13-positive acute myeloid leukemia (AML) cells proliferate abnormally and escape death. Here, we show that the CNGRC-GG-D(KLAKLAK)2 peptide induces death in AML cell lines (U937, THP-1, NB4, HL-60) and primary blood cells from AML patients. Cell death was characterized as a caspase-independent mechanism, without DNA fragmentation, but phosphatidylserine externalization and membrane disruption. Our results demonstrate in U937 cells that (i) the NGR-peptide triggers the loss of mitochondrial potential(ΔΨm) and generates superoxide anion (O2−), (ii) N-acetyl-L-cysteine (NAC) and extra/intracellular Ca2+ chelators (BAPTA) prevent both O2− production and cell death, (iii) the Ca2+-channel blocker nifedipine prevents cell death (indicating that Ca2+ influx is the initial death trigger), and (iv) BAPTA, but not NAC, prevents ΔΨm loss (suggesting O2− is a mitochondrial downstream effector). AML cell lines and primary blasts responding to the lethal action of NGR-peptide express promatrix metalloproteinase-12 (proMMP-12) and its substrate progranulin (an 88 kDa cell survival factor). A cell-free assay highlighted proMMP-12 activation by O2−. Accordingly, NGR-peptide's downregulation of 88 kDa progranulin protein was prevented by BAPTA and NAC. Conversely, AML blast resistance to NGR-peptide is associated with the expression of a distinct, 105 kDa progranulin isoform. These results indicate that CNGRC-GG-D(KLAKLAK)2 induces death in AML cells through the Ca2+-mitochondria-O2.-pathway, and support the link between proMMP-12 activation and progranulin cleavage during cell death. Our findings may have implications for the understanding of tumour biology and treatment. PMID:26655501

The CNGRC-GG-D(KLAKLAK)2 peptide induces a caspase-independent, Ca2+-dependent death in human leukemic myeloid cells by targeting surface aminopeptidase N/CD13.

PubMed

Bouchet, Sandrine; Tang, Ruoping; Fava, Fanny; Legrand, Ollivier; Bauvois, Brigitte

2016-04-12

The CD13 antigen's binding site for the Asn-Gly-Arg (NGR) motif enables NGR-containing chemotherapeutic drugs to be delivered to CD13-positive tumours. Human CD13-positive acute myeloid leukemia (AML) cells proliferate abnormally and escape death. Here, we show that the CNGRC-GG-D(KLAKLAK)2 peptide induces death in AML cell lines (U937, THP-1, NB4, HL-60) and primary blood cells from AML patients. Cell death was characterized as a caspase-independent mechanism, without DNA fragmentation, but phosphatidylserine externalization and membrane disruption. Our results demonstrate in U937 cells that (i) the NGR-peptide triggers the loss of mitochondrial potential(ΔΨm) and generates superoxide anion (O2-), (ii) N-acetyl-L-cysteine (NAC) and extra/intracellular Ca2+ chelators (BAPTA) prevent both O2- production and cell death, (iii) the Ca2+-channel blocker nifedipine prevents cell death (indicating that Ca2+ influx is the initial death trigger), and (iv) BAPTA, but not NAC, prevents ΔΨm loss (suggesting O2- is a mitochondrial downstream effector). AML cell lines and primary blasts responding to the lethal action of NGR-peptide express promatrix metalloproteinase-12 (proMMP-12) and its substrate progranulin (an 88 kDa cell survival factor). A cell-free assay highlighted proMMP-12 activation by O2-. Accordingly, NGR-peptide's downregulation of 88 kDa progranulin protein was prevented by BAPTA and NAC. Conversely, AML blast resistance to NGR-peptide is associated with the expression of a distinct, 105 kDa progranulin isoform. These results indicate that CNGRC-GG-D(KLAKLAK)2 induces death in AML cells through the Ca2+-mitochondria-O2.-pathway, and support the link between proMMP-12 activation and progranulin cleavage during cell death. Our findings may have implications for the understanding of tumour biology and treatment.

The incidence and survival of acute de novo leukaemias in Estonia and in a well-defined region of western Sweden during 1982-1996: a survey of patients aged > or =65 years.

PubMed

Luik, E; Palk, K; Everaus, H; Varik, M; Aareleid, T; Wennström, L; Juntikka, E-L; Safai-Kutti, S; Stockelberg, D; Holmberg, E; Kutti, J

2004-07-01

To compare the incidence and survival of acute de novo leukaemias with particular reference to political/socio-economic and environmental factors in two neighbouring countries over the three 5-year periods (1982-1996). The present report covers only patients diagnosed when aged > or =65 years. A well-defined area of Sweden, the so-called Western Swedish Health Care Region and Estonia. Population-wise, the western Swedish Region and Estonia are very similar; area-wise they are also well comparable. The number of acute de novo leukaemias was quite dissimilar in the two countries (Estonia, n = 137, Sweden, n = 354). The age standardized incidence rates regarding the total number of acute de novo leukaemias was 5.31 per 100,000 inhabitants/year for Estonia and 7.99 for Sweden, this difference being statistically significant. However, the difference was merely attributable to incidence rates as regards acute myeloblastic leukaemias (AML); on the contrary, differences as regards acute lymphoblastic leukaemias (ALL) and non-classifiable, undifferentiated or biphenotypic acute leukaemias (uAL) were negligible. The relative survival for the total material of patients was significantly higher for Swedish when compared with Estonian patients (P < 0.001). Thus, the relative survival for the total material of patients aged > or =65 years in Estonia at 1 year was 8.5% and at 3 years 3.5% respectively. The corresponding figures for the Swedish patients were considerably higher, 22.7 and 7.7% respectively. This difference, however, applied only for patients with AML (P < 0.001), whereas the results for patients with ALL and uAL were equally dismal. The results clearly reflect how political and socio-economic factors may influence the survival of acute leukemia patients in two neighbouring countries.

Feedback regulation in a stem cell model with acute myeloid leukaemia.

PubMed

Jiao, Jianfeng; Luo, Min; Wang, Ruiqi

2018-04-24

The haematopoietic lineages with leukaemia lineages are considered in this paper. In particular, we mainly consider that haematopoietic lineages are tightly controlled by negative feedback inhibition of end-product. Actually, leukemia has been found 100 years ago. Up to now, the exact mechanism is still unknown, and many factors are thought to be associated with the pathogenesis of leukemia. Nevertheless, it is very necessary to continue the profound study of the pathogenesis of leukemia. Here, we propose a new mathematical model which include some negative feedback inhibition from the terminally differentiated cells of haematopoietic lineages to the haematopoietic stem cells and haematopoietic progenitor cells in order to describe the regulatory mechanisms mentioned above by a set of ordinary differential equations. Afterwards, we carried out detailed dynamical bifurcation analysis of the model, and obtained some meaningful results. In this work, we mainly perform the analysis of the mathematic model by bifurcation theory and numerical simulations. We have not only incorporated some new negative feedback mechanisms to the existing model, but also constructed our own model by using the modeling method of stem cell theory with probability method. Through a series of qualitative analysis and numerical simulations, we obtain that the weak negative feedback for differentiation probability is conducive to the cure of leukemia. However, with the strengthening of negative feedback, leukemia will be more difficult to be cured, and even induce death. In contrast, strong negative feedback for differentiation rate of progenitor cells can promote healthy haematopoiesis and suppress leukaemia. These results demonstrate that healthy progenitor cells are bestowed a competitive advantage over leukaemia stem cells. Weak g 1 , g 2 , and h 1 enable the system stays in the healthy state. However, strong h 2 can promote healthy haematopoiesis and suppress leukaemia.

MYD88 Inhibitor ST2825 Suppresses the Growth of Lymphoma and Leukaemia Cells.

PubMed

Shiratori, Erika; Itoh, Mai; Tohda, Shuji

2017-11-01

Myeloid differentiation primary response gene 88 (MYD88), which activates the nuclear factor kappa B (NF-κB) pathway, is important for the growth of lymphoma and leukaemia cells. In this study, we investigated the effects of ST2825, a synthetic peptidomimetic compound which inhibits MYD88 homodimerization, on their growth. Seven lymphoma and leukaemia cell lines including TMD8, a B-cell lymphoma line with MYD88-activating mutation, were treated with ST2825 and analysed for cell proliferation and expression of NF-κB signalling-related molecules. ST2825 suppressed the growth of all cell lines by inducing apoptosis and down-regulating phosphorylation of NF-κB pathway components inhibitor of nuclear factor kappa B kinase (IκB) and reticuloendotheliosis oncogene A (RelA), as well as of MYD88 activator Bruton tyrosine kinase (BTK), suggesting that MYD88 may affect BTK activity. ST2825 effects were specific as MYD88-targeting siRNA also suppressed phosphorylation of NF-κB signalling proteins and BTK in TMD8 cells. ST2825 may be a novel drug targeting not only B-lymphoid malignancies with MYD88 mutations, but also lymphoma and leukaemia with wild-type MYD88. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

MAPK/AP-1-Targeted Anti-Inflammatory Activities of Xanthium strumarium.

PubMed

Hossen, Muhammad Jahangir; Kim, Mi-Yeon; Cho, Jae Youl

2016-01-01

Xanthium strumarium L. (Asteraceae), a traditional Chinese medicine, is prescribed to treat arthritis, bronchitis, and rhinitis. Although the plant has been used for many years, the mechanism by which it ameliorates various inflammatory diseases is not yet fully understood. To explore the anti-inflammatory mechanism of methanol extracts of X. strumarium (Xs-ME) and its therapeutic potential, we used lipopolysaccharide (LPS)-stimulated murine macrophage-like RAW264.7 cells and human monocyte-like U937 cells as well as a LPS/D-galactosamine (GalN)-induced acute hepatitis mouse model. To find the target inflammatory pathway, we used holistic immunoblotting analysis, reporter gene assays, and mRNA analysis. Xs-ME significantly suppressed the up-regulation of both the activator protein (AP)-1-mediated luciferase activity and the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1[Formula: see text], IL-6, and tumor necrosis factor (TNF)-[Formula: see text]. Moreover, Xs-ME strongly inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) in LPS-stimulated RAW264.7 and U937 cells. Additionally, these results highlighted the hepatoprotective and curative effects of Xs-ME in a mouse model of LPS/D-GalN-induced acute liver injury, as assessed by elevated serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and histological damage. Therefore, our results strongly suggest that the ethnopharmacological roles of Xs-ME in hepatitis and other inflammatory diseases might result from its inhibitory activities on the inflammatory signaling of MAPK and AP-1.

Magnolol inhibits tumor necrosis factor-α-induced ICAM-1 expression via suppressing NF-κB and MAPK signaling pathways in human lung epithelial cells.

PubMed

Chunlian, Wu; Heyong, Wang; Jia, Xu; Jie, Huang; Xi, Chen; Gentao, Liu

2014-12-01

Magnolol is a traditional Chinese medicine from the root and bark of Magnolia officinalis. It has long been used to treat anxiety, cough, headache and allergies, as well as a variety of inflammations. Lung inflammation is a key event in the pathogenesis of asthma and chronic obstructive pulmonary disease. The present study sought to examine the effects of magnolol on tumor necrosis factor (TNF)-α-induced upregulation of intercellular adhesion molecule-1 (ICAM-1), activation of the nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling pathway in cultured human pulmonary epithelial cells, and adhesion of human macrophage-like U937 cells to A549 cells. A549 cells were incubated with magnolol at 25 and 50 μmol/l. Then, 20 ng/ml TNF-α was used to activate the cells. Magnolol inhibited the growth of human pulmonary epithelial A549 cells in a dose- and time-dependent manner. Magnolol suppressed the adhesion of U937 cells to TNF-α-induced A549 cells. In cultured human pulmonary epithelial A549 cells, magnolol decreased TNF-α-induced upregulation of ICAM-1. Magnolol repressed TNF-α-induced activation of NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways in A549 cells by inhibiting phosphorylation of NF-κB, p38, extracellular signal-regulated kinase (ERK) 1/2, and stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK). These findings support the hypothesis that magnolol inhibits the inflammatory process in lung epithelial A549 cells by suppressing the ICAM-1 and NF-κB and MAPK signaling pathways. Taken together, these results indicate that magnolol offers significant potential as a therapeutic treatment for inflammatory diseases of the lungs including asthma, sepsis, and chronic obstructive pulmonary disease.

Epigallocatechin 3-gallate inhibits 7-ketocholesterol-induced monocyte-endothelial cell adhesion.

PubMed

Yamagata, Kazuo; Tanaka, Noriko; Suzuki, Koichi

2013-07-01

7-Ketocholesterol (7KC) induces monocytic adhesion to endothelial cells, and induces arteriosclerosis while high-density lipoprotein (HDL) inhibits monocytic adhesion to the endothelium. Epigallocatechin 3-gallate (EGCG) was found to have a protective effect against arteriosclerosis. Therefore, the purpose of this study was to examine the possible HDL-like mechanisms of EGCG in endothelial cells by investigating whether EGCG inhibits 7KC-induced monocyte-endothelial cell adhesion by activating HDL-dependent signal transduction pathways. 7KC and/or EGCG were added to human endothelial cells (ISO-HAS), and the adhesion of pro-monocytic U937 cells was examined. The expression of genes associated with HDL effects such as Ca(2+)/calmodulin-dependent kinase II (CaMKKII), liver kinase B (LKD1), PSD-95/Dlg/ZO-1 kinase 1 (PDZK1), phosphatidylinositol 3-kinase (PI3K), intercellular adhesion molecule-1 (ICAM-1), monocyte chemotactic protein-1 (MCP-1), and endothelial nitric oxide synthase (eNOS) was examined by RT-PCR, and ICAM-1 protein expression was evaluated by western blot (WB). Production of reactive oxygen species (ROS) was examined with H2DCFDA. 7KC significantly induced adhesion of U937 cells to human endothelial cells while significantly increasing gene expressions of ICAM-1 and MCP-1 and decreasing eNOS and CaMKKII gene expressions. EGCG inhibited 7KC-induced monocytic adhesion to endothelial cells, and induced expression of eNOS and several genes involved in the CaMKKII pathway. Stimulation of endothelial cells with EGCG produced intracellular ROS, whereas treatment with N-acetylcysteine (NAC) blocked EGCG-induced expression of eNOS and CaMKKII. These results suggest that inhibition of monocyte-endothelial cell adhesion by EGCG is associated with CaMKKII pathway activation by ROS. Inhibition of 7KC-induced monocyte-endothelial cell adhesion induced by EGCG may function similarly to HDL. Copyright © 2013 Elsevier Inc. All rights reserved.

Abundant and equipotent founder cells establish and maintain acute lymphoblastic leukaemia.

PubMed

Elder, A; Bomken, S; Wilson, I; Blair, H J; Cockell, S; Ponthan, F; Dormon, K; Pal, D; Heidenreich, O; Vormoor, J

2017-12-01

High frequencies of blasts in primary acute lymphoblastic leukaemia (ALL) samples have the potential to induce leukaemia and to engraft mice. However, it is unclear how individual ALL cells each contribute to drive leukaemic development in a bulk transplant and the extent to which these blasts vary functionally. We used cellular barcoding as a fate mapping tool to track primograft ALL blasts in vivo. Our results show that high numbers of ALL founder cells contribute at similar frequencies to leukaemic propagation over serial transplants, without any clear evidence of clonal succession. These founder cells also exhibit equal capacity to home and engraft to different organs, although stochastic processes may alter the composition in restrictive niches. Our findings enhance the stochastic stem cell model of ALL by demonstrating equal functional abilities of singular ALL blasts and show that successful treatment strategies must eradicate the entire leukaemic cell population.

Measurable residual disease testing in acute myeloid leukaemia.

PubMed

Hourigan, C S; Gale, R P; Gormley, N J; Ossenkoppele, G J; Walter, R B

2017-07-01

There is considerable interest in developing techniques to detect and/or quantify remaining leukaemia cells termed measurable or, less precisely, minimal residual disease (MRD) in persons with acute myeloid leukaemia (AML) in complete remission defined by cytomorphological criteria. An important reason for AML MRD-testing is the possibility of estimating the likelihood (and timing) of leukaemia relapse. A perfect MRD-test would precisely quantify leukaemia cells biologically able and likely to cause leukaemia relapse within a defined interval. AML is genetically diverse and there is currently no uniform approach to detecting such cells. Several technologies focused on immune phenotype or cytogenetic and/or molecular abnormalities have been developed, each with advantages and disadvantages. Many studies report a positive MRD-test at diverse time points during AML therapy identifies persons with a higher risk of leukaemia relapse compared with those with a negative MRD-test even after adjusting for other prognostic and predictive variables. No MRD-test in AML has perfect sensitivity and specificity for relapse prediction at the cohort- or subject levels and there are substantial rates of false-positive and -negative tests. Despite these limitations, correlations between MRD-test results and relapse risk have generated interest in MRD-test result-directed therapy interventions. However, convincing proof that a specific intervention will reduce relapse risk in persons with a positive MRD-test is lacking and needs testing in randomized trials. Routine clinical use of MRD-testing requires further refinements and standardization/harmonization of assay platforms and results reporting. Such data are needed to determine whether results of MRD-testing can be used as a surrogate end point in AML therapy trials. This could make drug-testing more efficient and accelerate regulatory approvals. Although MRD-testing in AML has advanced substantially, much remains to be done.

Effect of Bee Venom and Its Fractions on the Release of Pro-Inflammatory Cytokines in PMA-Differentiated U937 Cells Co-Stimulated with LPS

PubMed Central

Tusiimire, Jonans; Wallace, Jennifer; Woods, Nicola; Dufton, Mark J.; Parkinson, John A.; Abbott, Grainne; Clements, Carol J.; Young, Louise; Park, Jin Kyu; Jeon, Jong Woon; Ferro, Valerie A.; Watson, David G.

2016-01-01

The venom of Apis mellifera (honey bee) has been reported to play a role in immunotherapy, but existing evidence to support its immuno-modulatory claims is insufficient. Four fractions from whole bee venom (BV) were separated using medium pressure liquid chromatography. Their ability to induce the production of cytokines TNFα, IL-1β and IL-6 in phorbol-12-myristate-13-acetate (PMA)-treated U937 cells was assessed. The levels of the three cytokines produced by stimulation with the four fractions and crude BV without LPS were not significantly different from negative control values. However, co-stimulation of the cells with LPS and Fraction 4 (F-4) induced a 1.6-fold increase in TNF-α level (p < 0.05) compared to LPS alone. Likewise, LPS-induced IL-1β production was significantly synergised in the presence of F-1 (nine-fold), F-2 (six-fold), F-3 (four-fold) and F-4 (two-fold) fractions, but was only slightly enhanced with crude BV (1.5-fold) relative to LPS. Furthermore, the LPS-stimulated production of IL-6 was not significantly increased in cells co-treated with F-2 and F-3, but the organic fraction (F-4) showed an inhibitory effect (p < 0.05) on IL-6 production. The latter was elucidated by NMR spectroscopy and found to contain(Z)-9-eicosen-1-ol. The effects observed with the purified BV fractions were more marked than those obtained with the crude sample. PMID:27104574

Antimicrobial Properties and Cytotoxicity of Sulfated (1,3)-β-D-Glucan from the Mycelium of the Mushroom Ganoderma lucidum.

PubMed

Wan-Mohtar, Wan Abd Al Qadr Imad; Young, Louise; Abbott, Gráinne M; Clements, Carol; Harvey, Linda M; McNeil, Brian

2016-06-28

Ganoderma lucidum BCCM 31549 has a long established role for its therapeutic activities. In this context, much interest has focused on the possible functions of the (1,3)-β-D-glucan (G) produced by these cultures in a stirred-tank bioreactor and extracted from their underutilized mycelium. In the existing study, we report on the systematic production of G, and its sulfated derivative (GS). The aim of this study was to investigate G and its GS from G. lucidum in terms of their antibacterial properties and cytotoxicity spectrum against human prostate cells (PN2TA) and human caucasian histiocytic lymphoma cells (U937). (1)H NMR for both G and GS compounds showed β-glycosidic linkages and structural similarities when compared with two standards (laminarin and fucoidan). The existence of characteristic absorptions at 1,170 and 867 cm(-1) in the FTIR (Fourier Transform Infrared Spectroscopy) for GS demonstrated the successful sulfation of G. Only GS exhibited antimicrobial activity against a varied range of test bacteria of relevance to foodstuffs and human health. Moreover, both G and GS did not show any cytotoxic effects on PN2TA cells, thus helping demonstrate the safety of these polymers. Moreover, GS showed 40% antiproliferation against cancerous U937 cells at the low concentration (60 μg/ ml) applied in this study compared with G (10%). Together, this demonstrates that sulfation clearly improved the solubility and therapeutic activities of G. The water-soluble GS demonstrates the potential multifunctional effects of these materials in foodstuffs.

Regulation of CYBB Gene Expression in Human Phagocytes by a Distant Upstream NF-κB Binding Site.

PubMed

Frazão, Josias B; Thain, Alison; Zhu, Zhiqing; Luengo, Marcos; Condino-Neto, Antonio; Newburger, Peter E

2015-09-01

The human CYBB gene encodes the gp91-phox component of the phagocyte oxidase enzyme complex, which is responsible for generating superoxide and other downstream reactive oxygen species essential to microbial killing. In the present study, we have identified by sequence analysis a putative NF-κB binding site in a DNase I hypersensitive site, termed HS-II, located in the distant 5' flanking region of the CYBB gene. Electrophoretic mobility assays showed binding of the sequence element by recombinant NF-κB protein p50 and by proteins in nuclear extract from the HL-60 myeloid leukemia cell line corresponding to p50 and to p50/p65 heterodimers. Chromatin immunoprecipitation demonstrated NF-κB binding to the site in intact HL-60 cells. Chromosome conformation capture (3C) assays demonstrated physical interaction between the NF-κB binding site and the CYBB promoter region. Inhibition of NF-κB activity by salicylate reduced CYBB expression in peripheral blood neutrophils and differentiated U937 monocytic leukemia cells. U937 cells transfected with a mutant inhibitor of κB "super-repressor" showed markedly diminished CYBB expression. Luciferase reporter analysis of the NF-κB site linked to the CYBB 5' flanking promoter region revealed enhanced expression, augmented by treatment with interferon-γ. These studies indicate a role for this distant, 15 kb upstream, binding site in NF-κB regulation of the CYBB gene, an essential component of phagocyte-mediated host defense. © 2015 Wiley Periodicals, Inc.

Chronic neutrophilic leukaemia and plasma cell-related neutrophilic leukaemoid reactions.

PubMed

Bain, Barbara J; Ahmad, Shahzaib

2015-11-01

Many cases reported as 'chronic neutrophilic leukaemia' have had an associated plasma cell neoplasm. Recent evidence suggests that the great majority of such cases represent a neutrophilic leukaemoid reaction to the underlying multiple myeloma or monoclonal gammopathy of undetermined significance. We have analysed all accessible reported cases to clarify the likely diagnosis and to ascertain whether toxic granulation, Döhle bodies and an increased neutrophil alkaline phosphatase score were useful in making a distinction between chronic neutrophilic leukaemia and a neutrophilic leukaemoid reaction. We established that all these changes occur in both conditions. Toxic granulation and Döhle bodies are more consistently present in leukaemoid reactions but also occur quite frequently in chronic neutrophilic leukaemia. The neutrophil alkaline phosphatase score is increased in both conditions and is of no value in making a distinction. © 2015 John Wiley & Sons Ltd.

Couches minces organiques riches en amines primaires par photo-polymerisation ultraviolette : Caracterisation et applications biomedicales

NASA Astrophysics Data System (ADS)

St-Georges-Robillard, Amelie

Biomaterials have evolved significantly over the past decades. There are now several types of polymeric biomaterials with physical characteristics suited to different applications. This project focuses on improving the physico-chemical properties of the surface of these materials by incorporating primary amines (R-NH2), a functional group known to promote adhesion and cell growth, in the context of two biomedical applications. First, it is necessary to develop a cell culture surface that enables the adhesion of U937 monocytes. These cells are used to evaluate the effect of wear particles produced by the prosthesis in periprosthetic osteolysis, a major cause of failure of a hip replacement. Second, one of the strategies used to improve the success rate of polymeric vascular grafts is to create a layer of endothelial cells on the lumen of the prosthesis. A coating that promotes the adhesion and growth of human umbilical vein endothelial cells (HUVEC) is required to achieve that layer. Previous studies have demonstrated that the addition of R-NH2 groups on the coating allows the adhesion of U937 monocytes, provided that their concentration [NH2] is higher than a certain critical value, [NH2]crit; R-NH2 groups were also found to enhance the adhesion and proliferation of HUVEC. Two different primary amine-rich coatings are investigated in this work: organic thin films deposited by vacuum ultraviolet (VUV) photo-polymerization, UV-PE:N; and parylene diX AM, deposited by chemical vapor deposition (CVD). The physico-chemical stability of these coatings in air and in water, essential for biomedical applications, was first studied. “Aging” of parylene diX AM in contact with the ambient air caused a diminution of [NH2]/[C] of around 6 % during 22 days and is caused by the oxidation of R-NH2 by atmospheric oxygen, while in the case of UV-PE:N, the diminution is only of 2,5 % over 26 days. Also, a second aging mechanism is present: the reaction of trapped free radicals in the coating with oxygen in air or dissolved in water. The UV-PE:N coating proved virtually insoluble, despite a high concentration of nitrogen and showed excellent retention of the R-NH 2 groups when immersed in water, two essential properties for applications in cell culture. These studies have also shown that UV-PE:N coatings (deposited with two gas ratios, R = 0.75 and 1) permit adhesion and survival of U937 monocytes without causing any significant inflammatory response, which enables one to study wear particle effects. However, the adhesion of U937 monocytes on parylene diX AM manifests a rather different behavior, adhesion being proportional to [NH2] and not controlled by the critical threshold, [NH 2]crit, observed for different types of plasma-polymer coatings. Also, monocytes do not survive for 24 hours on parylene diX AM. The cause for these differences remains to be elucidated. Finally, the adhesion and growth of HUVEC on both types of UV-PE:N (R = 0.75 and 1), as well as on L-PPE:N and on gelatinized polystyrene, were statistically higher than on untreated PET. Therefore, UV-PE:N has proven to be a cell culture surface well-adapted for HUVEC, of similar efficiency to gelatinized polystyrene, a surface known to promote the adhesion and growth of HUVEC. UV-PE: N is therefore a promising coating that provides stability in air and in water for use in cell culture and has demonstrated its performance for two biomedical applications. Keywords: biomaterials, primary amines, thin film deposition, photo-polymerization, plasma polymerization, XPS, chemical derivatization, ellipsometry, cellular adhesion, arthroplasty, vascular graft.

Changes in protein expression of U937 and Jurkat cells exposed to nanosecond pulsed electric fields

NASA Astrophysics Data System (ADS)

Moen, Erick K.; Roth, Caleb C.; Cerna, Caesar; Estalck, Larry; Wilmink, Gerald; Ibey, Bennett L.

2013-02-01

Application of nanosecond pulsed electric fields (nsPEF) to various biological cell lines has been to shown to cause many diverse effects, including poration of the plasma membrane, depolarization of the mitochondrial membrane, blebbing, apoptosis, and intracellular calcium bursts. The underlying mechanism(s) responsible for these diverse responses are poorly understood. Of specific interest in this paper are the long-term effects of nsPEF on cellular processes, including the regulation of genes and production of proteins. Previous studies have reported transient activation of select signaling pathways involving mitogen-activated protein kinases (MAPKs), protein phosphorylation and downstream gene expression following nsPEF application. We hypothesize that nsPEF represents a unique stimulus that could be used to externally modulate cellular processes. To validate our hypothesis, we performed a series of cuvette-based exposures at 10 and 600ns pulse widths using a custom Blumlien line pulser system. We measured acute changes in the plasma membrane structure using flow cytometry by tracking phosphatidylserine externalization via FITC-Annexin V labeling and poration via propidium iodide uptake. We then compared these results to viability of the cells at 24 hours post exposure using MTT assay and changes in the MAPK family of proteins at 8 hours post-exposure using Luminex assay. By comparing exposures at 10 and 600ns duration, we found that most MAPK family-protein expression increased in Jurkat and U937 cell lines following exposure and compared well with drops in viability and changes in plasma membrane asymmetry. What proved interesting is that some MAPK family proteins (e.g. p53, STAT1), were expressed in one cell line, but not the other. This difference may point to an underlying mechanism for observed difference in cellular sensitivity to nsPEFinduced stresses.

Calcium-dependent mitochondrial formation of species mediating DNA single strand breakage in U937 cells exposed to sublethal concentrations of tert-butylhydroperoxide.

PubMed

Guidarelli, A; Clementi, E; Sciorati, C; Cattabeni, F; Cantoni, O

1997-10-01

Treatment of U937 cells with a sublethal albeit DNA-damaging concentration of tert-butylhydroperoxide (tB-OOH) enhanced mitochondrial Ca++ uptake and ruthenium red (RR), a polycation that inhibits the calcium uniporter of mitochondria, significantly reduced the extent of DNA cleavage generated by the hydroperoxide. Release of Ca++ from the ryanodine(Ry)/caffeine(Cf)-sensitive stores further increased mitochondrial Ca++ uptake and elicited a parallel enhancement in DNA strand scission induced by tB-OOH that was prevented by both Ry and RR. DNA damage caused by tB-OOH alone or associated with either Cf or RR was prevented by iron chelators, insensitive to antioxidants and repaired with kinetics superimposable with those observed after treatment with H2O2. Cf enhanced the DNA-damaging effects of tB-OOH in permeabilized cells as well, and similar effects were observed upon addition of CaCl2. Cf did not further increase the formation of DNA lesions elicited by tB-OOH in the presence of CaCl2. The enhancing effects of Cf were prevented by RR and ryanodine, whereas those mediated by exogenous calcium were prevented only by RR. DNA strand scission caused by tB-OOH alone or associated with Cf in the permeabilized cell system was severely inhibited by ethylene glycol-bis(beta-aminoethyl ether)-N, N,N',N'-tetraacetic acid. The mechanism(s) whereby Ca++ promotes the mitochondrial formation of species that will ultimately result in the formation of DNA lesions was subsequently analyzed using intact as well as permeabilized cells. Hydrogen peroxide was identified to be one of these species.

Acute promyelocytic leukaemia: novel insights into the mechanisms of cure.

PubMed

de Thé, Hugues; Chen, Zhu

2010-11-01

The fusion oncogene, promyelocytic leukaemia (PML)-retinoic acid receptor-α (RARA), initiates acute promyelocytic leukaemia (APL) through both a block to differentiation and increased self-renewal of leukaemic progenitor cells. The current standard of care is retinoic acid (RA) and chemotherapy, but arsenic trioxide also cures many patients with APL, and an RA plus arsenic trioxide combination cures most patients. This Review discusses the recent evidence that reveals surprising new insights into how RA and arsenic trioxide cure this leukaemia, by targeting PML-RARα for degradation. Drug-triggered oncoprotein degradation may be a strategy that is applicable to many cancers.

Complement activation by carbon nanotubes and its influence on the phagocytosis and cytokine response by macrophages.

PubMed

Pondman, Kirsten M; Sobik, Martin; Nayak, Annapurna; Tsolaki, Anthony G; Jäkel, Anne; Flahaut, Emmanuel; Hampel, Silke; Ten Haken, Bennie; Sim, Robert B; Kishore, Uday

2014-08-01

Carbon nanotubes (CNTs) have promised a range of applications in biomedicine. Although influenced by the dispersants used, CNTs are recognized by the innate immune system, predominantly by the classical pathway of the complement system. Here, we confirm that complement activation by the CNT used continues up to C3 and C5, indicating that the entire complement system is activated including the formation of membrane-attack complexes. Using recombinant forms of the globular regions of human C1q (gC1q) as inhibitors of CNT-mediated classical pathway activation, we show that C1q, the first recognition subcomponent of the classical pathway, binds CNTs via the gC1q domain. Complement opsonisation of CNTs significantly enhances their uptake by U937 cells, with concomitant downregulation of pro-inflammatory cytokines and up-regulation of anti-inflammatory cytokines in both U937 cells and human monocytes. We propose that CNT-mediated complement activation may cause recruitment of cellular infiltration, followed by phagocytosis without inducing a pro-inflammatory immune response. This study highlights the importance of the complement system in response to carbon nanontube administration, suggesting that the ensuing complement activation may cause recruitment of cellular infiltration, followed by phagocytosis without inducing a pro-inflammatory immune response. Copyright © 2014 Elsevier Inc. All rights reserved.

Legionella pneumophila mutants that are defective for iron acquisition and assimilation and intracellular infection.

PubMed Central

Pope, C D; O'Connell, W; Cianciotto, N P

1996-01-01

Legionella pneumophila, a parasite of macrophages and protozoa, requires iron for optimal extracellular and intracellular growth. However, its mechanisms of iron acquisition remain uncharacterized. Using mini-Tn10 mutagenesis, we isolated 17 unique L. pneumophila strains which appeared to be defective for iron acquisition and assimilation. Eleven of these mutants were both sensitive to the iron chelator ethylenediamine di(o-hydroxyphenylacetic acid) and resistant to streptonigrin, an antibiotic whose lethal effect requires high levels of intracellular iron. Six mutants were also defective for the infection of macrophage-like U937 cells. Although none were altered in entry, mutants generally exhibited prolonged lag phases and in some cases replicated at slower rates. Overall, the reduced recoveries of mutants, relative to that of the wild type, ranged from 3- to 1,000-fold. Strain NU216, the mutant displaying the most severe lag phase and the slowest rate of replication, was studied further. Importantly, within U937 cells, NU216 was approximately 100-fold more sensitive than the wild type was to treatment with the Fe3+ chelator deferoxamine, indicating that it is defective for intracellular iron acquisition and assimilation. Furthermore, this strain was unable to mediate any cytopathic effect and was impaired for infectivity of an amoebal host. Taken together, the isolation of these mutants offers genetic proof that iron acquisition and assimilation are critical for intracellular infection by L. pneumophila. PMID:8550218

Biochemical characterization and antioxidant and antiproliferative activities of different Ganoderma collections.

PubMed

Saltarelli, Roberta; Ceccaroli, Paola; Buffalini, Michele; Vallorani, Luciana; Casadei, Lucia; Zambonelli, Alessandra; Iotti, Mirco; Badalyan, Susanna; Stocchi, Vilberto

2015-01-01

The aim of this study was to conduct a molecular and biochemical characterization and to compare the antioxidant and antiproliferative activities of four Ganoderma isolates belonging to Ganoderma lucidum (Gl-4, Gl-5) and Ganoderma resinaceum (F-1, F-2) species. The molecular identification was performed by ITS and IGS sequence analyses and the biochemical characterization by enzymatic and proteomic approaches. The antioxidant activity of the ethanolic extracts was compared by three different methods and their flavonoid contents were also analyzed by high-performance liquid chromatography. The antiproliferative effect on U937 cells was determined by MTT assay. The studied mycelia differ both in the enzymatic activities and protein content. The highest content in total phenol and the highest antioxidant activity for DPPH free radical scavenging and chelating activity on Fe(2+) were observed with the Gl-4 isolate of G. lucidum. The presence of quercetin, rutin, myricetin, and morin as major flavonoids with effective antioxidant activity was detected. The ethanolic extracts from mycelia of G. lucidum isolates possess a substantial antiproliferative activity against U937 cells in contrast to G. resinaceum in which the antiproliferative effects were insignificant. This study provides a comparison between G. lucidum and G. resinaceum mycelial strains, and shows that G. resinaceum could be utilized to obtain several bioactive compounds. © 2015 S. Karger AG, Basel.

Biomimetic nanoparticles for siRNA delivery in the treatment of leukaemia.

PubMed

Guo, Jianfeng; Cahill, Mary R; McKenna, Sharon L; O'Driscoll, Caitriona M

2014-12-01

Leukaemia is a bone marrow cancer occurring in acute and chronic subtypes. Acute leukaemia is a rapidly fatal cancer potentially causing death within a few weeks, if untreated. Leukaemia arises as a result of disruption to haematopoietic precursors, caused either by acquired gene fusions, gene mutations or inappropriate expression of the relevant oncogenes. Current treatment options have made significant progress, but the 5 year survival for acute leukaemia remains under 10% in elderly patients, and less than 50% for some types of acute leukaemia in younger adults. For chronic leukaemias longer survival is generally expected and for chronic myeloid leukaemia patients on tyrosine kinase inhibitors the median survival is not yet reached and is expected to exceed 10 years. Chemotherapy and haematopoietic stem cell transplantation (HSCT) for acute leukaemia provide the mainstay of therapy for patients under 65 and both carry significant morbidity and mortality. Alternative and superior therapeutic strategies for acute leukaemias are urgently required. Recent molecular-based knowledge of recurring chromosome rearrangements, in particular translocations and inversions, has resulted in significant advances in understanding the molecular pathogenesis of leukaemia. Identification of a number of unique fusion genes has facilitated the development of highly specific small interfering RNAs (siRNA). Although delivery of siRNA using multifunctional nanoparticles has been investigated to treat solid cancers, the application of this approach to blood cancers is at an early stage. This review describes current treatments for leukaemia and highlights the potential of leukaemic fusion genes as therapeutic targets for RNA interference (RNAi). In addition, the design of biomimetic nanoparticles which are capable of responding to the physiological environment of leukaemia and their potential to advance RNAi therapeutics to the clinic will be critically evaluated. Copyright © 2014 Elsevier Inc. All rights reserved.

Interleukin 4 receptor signaling in human monocytes and U937 cells involves the activation of a phosphatidylcholine-specific phospholipase C: a comparison with chemotactic peptide, FMLP, phospholipase D, and sphingomyelinase

PubMed Central

1994-01-01

Interleukin 4 (IL-4) diminishes cytokine activation of human macrophage. IL-4 binding to monocyte IL-4R is associated with protein kinase C (PKC) translocation to a nuclear fraction. The cleavage of diacyglycerol (DAG), an activator of PKC, from membrane phospholipids was investigated to define the proximal events of IL-4R signaling. IL-4 induced a statistically significant time-and dose-dependent generation of DAG. The IL-4-triggered production of DAG was not derived from phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis, since neither cytosolic calcium flux nor liberation of inositol phosphates was detected in response to IL-4. Experiments were performed using [14C- methyl]choline-labeled U937 cells and monocytes to determine whether IL- 4R activated phospholipase C (PLC), PLD, or PLA2 to use membrane phosphatidylcholine (PC) to form DAG. IL-4 induced a time- and dose- dependent increase of phosphocholine (pchol) with concomitant degradation of membrane PC (p < 0.05 compared with control). The finding that the peak reduction of PC was equivalent to peak production of pchol suggested that IL-4R signaling involved the activation of a PC- specific PLC. Changes in choline (chol) or lyso-PC and glycerolphosphocholine, the respective products of PC cleavage by PLD or PLA2, were not detected in IL-4-treated cells. In contrast, exogenous PLD induced an increase in chol and concomitant loss of membrane PC. Additional investigation suggested that IL-4R signaling does not involve PLD. In cells labeled with L-lyso-3-PC 1-[1- 14C]palmitoyl, PLD but not IL-4, increased the production of phosphatidic acid (PA) and phosphatidyl-ethanol when pretreated with ethanol. Propranolol, an inhibitor of phosphatidate phosphohydrolase, and calyculin A, a phosphatase 1 and 2A inhibitor, blocked DAG production in response to FMLP but not to IL-4. In propranolol pretreated cells, PMA but not IL-4 triggered the production of PA and lowered the amount of DAG. Evidence that PLA2 is not coupled to IL-4R is the detection of arachidonate production in response to FMLP but not to IL-4. Furthermore, IL-4R is not coupled to sphingomyelinase (SMase) since IL-4, unlike exogenous SMase, did not generate ceramide but induced the hydrolysis of PC to pchol that was comparable to exogenous PLC. In summary, IL-4R signaling in monocytes and U937 cells involves PLC and not PLD, PLA2, or SMase, and it uses PC and not PIP2 to form DAG. PMID:7931078

Towards an understanding of the biology and targeted treatment of paediatric relapsed acute lymphoblastic leukaemia.

PubMed

Irving, Julie A E

2016-03-01

Acute lymphoblastic leukaemia is the most common childhood cancer and for those children who relapse, prognosis is poor and new therapeutic strategies are needed. Recurrent pathways implicated in relapse include RAS, JAK STAT, cell cycle, epigenetic regulation, B cell development, glucocorticoid response, nucleotide metabolism and DNA repair. Targeting these pathways is a rational therapeutic strategy and may deliver novel, targeted therapies into the clinic. Relapse often stems from a minor clone present at diagnosis and thus analysis of persisting leukaemia during upfront therapy may allow targeted drug intervention to prevent relapse. © 2015 John Wiley & Sons Ltd.

Deregulated hedgehog pathway signaling is inhibited by the smoothened antagonist LDE225 (Sonidegib) in chronic phase chronic myeloid leukaemia

PubMed Central

Irvine, David A.; Zhang, Bin; Kinstrie, Ross; Tarafdar, Anuradha; Morrison, Heather; Campbell, Victoria L.; Moka, Hothri A.; Ho, Yinwei; Nixon, Colin; Manley, Paul W.; Wheadon, Helen; Goodlad, John R.; Holyoake, Tessa L.; Bhatia, Ravi; Copland, Mhairi

2016-01-01

Targeting the Hedgehog (Hh) pathway represents a potential leukaemia stem cell (LSC)-directed therapy which may compliment tyrosine kinase inhibitors (TKIs) to eradicate LSC in chronic phase (CP) chronic myeloid leukaemia (CML). We set out to elucidate the role of Hh signaling in CP-CML and determine if inhibition of Hh signaling, through inhibition of smoothened (SMO), was an effective strategy to target CP-CML LSC. Assessment of Hh pathway gene and protein expression demonstrated that the Hh pathway is activated in CD34+ CP-CML stem/progenitor cells. LDE225 (Sonidegib), a small molecule, clinically investigated SMO inhibitor, used alone and in combination with nilotinib, inhibited the Hh pathway in CD34+ CP-CML cells, reducing the number and self-renewal capacity of CML LSC in vitro. The combination had no effect on normal haemopoietic stem cells. When combined, LDE225 + nilotinib reduced CD34+ CP-CML cell engraftment in NSG mice and, upon administration to EGFP+ /SCLtTA/TRE-BCR-ABL mice, the combination enhanced survival with reduced leukaemia development in secondary transplant recipients. In conclusion, the Hh pathway is deregulated in CML stem and progenitor cells. We identify Hh pathway inhibition, in combination with nilotinib, as a potentially effective therapeutic strategy to improve responses in CP-CML by targeting both stem and progenitor cells. PMID:27157927

Clinical effect of stereotyped B-cell receptor immunoglobulins in chronic lymphocytic leukaemia: a retrospective multicentre study.

PubMed

Baliakas, Panagiotis; Hadzidimitriou, Anastasia; Sutton, Lesley-Ann; Minga, Eva; Agathangelidis, Andreas; Nichelatti, Michele; Tsanousa, Athina; Scarfò, Lydia; Davis, Zadie; Yan, Xiao-Jie; Shanafelt, Tait; Plevova, Karla; Sandberg, Yorick; Vojdeman, Fie Juhl; Boudjogra, Myriam; Tzenou, Tatiana; Chatzouli, Maria; Chu, Charles C; Veronese, Silvio; Gardiner, Anne; Mansouri, Larry; Smedby, Karin E; Pedersen, Lone Bredo; van Lom, Kirsten; Giudicelli, Véronique; Francova, Hana Skuhrova; Nguyen-Khac, Florence; Panagiotidis, Panagiotis; Juliusson, Gunnar; Angelis, Lefteris; Anagnostopoulos, Achilles; Lefranc, Marie-Paule; Facco, Monica; Trentin, Livio; Catherwood, Mark; Montillo, Marco; Geisler, Christian H; Langerak, Anton W; Pospisilova, Sarka; Chiorazzi, Nicholas; Oscier, David; Jelinek, Diane F; Darzentas, Nikos; Belessi, Chrysoula; Davi, Frederic; Rosenquist, Richard; Ghia, Paolo; Stamatopoulos, Kostas

2014-11-01

About 30% of cases of chronic lymphocytic leukaemia (CLL) carry quasi-identical B-cell receptor immunoglobulins and can be assigned to distinct stereotyped subsets. Although preliminary evidence suggests that B-cell receptor immunoglobulin stereotypy is relevant from a clinical viewpoint, this aspect has never been explored in a systematic manner or in a cohort of adequate size that would enable clinical conclusions to be drawn. For this retrospective, multicentre study, we analysed 8593 patients with CLL for whom immunogenetic data were available. These patients were followed up in 15 academic institutions throughout Europe (in Czech Republic, Denmark, France, Greece, Italy, Netherlands, Sweden, and the UK) and the USA, and data were collected between June 1, 2012, and June 7, 2013. We retrospectively assessed the clinical implications of CLL B-cell receptor immunoglobulin stereotypy, with a particular focus on 14 major stereotyped subsets comprising cases expressing unmutated (U-CLL) or mutated (M-CLL) immunoglobulin heavy chain variable genes. The primary outcome of our analysis was time to first treatment, defined as the time between diagnosis and date of first treatment. 2878 patients were assigned to a stereotyped subset, of which 1122 patients belonged to one of 14 major subsets. Stereotyped subsets showed significant differences in terms of age, sex, disease burden at diagnosis, CD38 expression, and cytogenetic aberrations of prognostic significance. Patients within a specific subset generally followed the same clinical course, whereas patients in different stereotyped subsets-despite having the same immunoglobulin heavy variable gene and displaying similar immunoglobulin mutational status-showed substantially different times to first treatment. By integrating B-cell receptor immunoglobulin stereotypy (for subsets 1, 2, and 4) into the well established Döhner cytogenetic prognostic model, we showed these, which collectively account for around 7% of all cases of CLL and represent both U-CLL and M-CLL, constituted separate clinical entities, ranging from very indolent (subset 4) to aggressive disease (subsets 1 and 2). The molecular classification of chronic lymphocytic leukaemia based on B-cell receptor immunoglobulin stereotypy improves the Döhner hierarchical model and refines prognostication beyond immunoglobulin mutational status, with potential implications for clinical decision making, especially within prospective clinical trials. European Union; General Secretariat for Research and Technology of Greece; AIRC; Italian Ministry of Health; AIRC Regional Project with Fondazione CARIPARO and CARIVERONA; Regione Veneto on Chronic Lymphocytic Leukemia; Nordic Cancer Union; Swedish Cancer Society; Swedish Research Council; and National Cancer Institute (NIH). Copyright © 2014 Elsevier Ltd. All rights reserved.

T-cell acute lymphoblastic leukaemia after liver transplantation: post-transplant lymphoproliferative disorder or coincidental de novo leukaemia?

PubMed

Fang, Yanan; Pinkney, Kerice A; Lee, John C; Gindin, Tatyana; Weiner, Michael A; Alobeid, Bachir; Bhagat, Govind

2013-03-01

Post-transplant lymphoproliferative disorders of T-cell origin are quite uncommon, and the vast majority represent neoplasms of mature, post-thymic T- or natural killer cells. Here, we report a rare case of T-cell acute lymphoblastic leukaemia (T-ALL), which occurred in an 18-year-old man who had undergone three liver transplants, initially for biliary atresia and subsequently for graft failure due to chronic rejection. He had received immunosuppression with cyclosporine and tacrolimus, as well as short-term treatment with OKT3. The T-ALL occurred 16 years after the first liver transplant. This case highlights the challenge for classifying rare neoplasms occurring in recipients of solid organ transplants that are currently not recognized to lie within the spectrum of post-transplant lymphoproliferative disorders. Given the long interval between the liver transplants and the development of T-ALL, a coincidental occurrence of the leukaemia cannot be ruled out. However, the potential roles of immunosuppressive therapy and other co-morbid conditions of the individual as possible risk factors for the pathogenesis of T-ALL are discussed. Copyright © 2012 John Wiley & Sons, Ltd.

Mortality from leukaemia and cancer in shipyard nuclear workers.

PubMed

Najarian, T; Colton, T

1978-05-13

A review of death certificates in New Hampshire, Maine, and Massachusetts for 1959-77 yielded a total of 1722 deaths among former workers at the Portsmouth Naval Shipyard where nuclear submarines are repaired and refuelled. Next of kin were contacted for 592. All deaths under age 80 were classified as being in former nuclear or non-nuclear workers depending on information supplied by next of kin. With U.S. age-specific proportional cancer mortality for White males as a standard, the observed/expected ratio of leukaemia deaths was 5.62 (6 observed, 1.1 expected) among the 146 former nuclear workers. For all cancer deaths, this ratio was 1.78. Among non-nuclear workers there was no statistically significant increase in proportional mortality from either leukaemia or from all cancers. The excess proportional leukaemia and cancer mortality among nuclear workers exceeds predictions based on previous data of radiation effects in man.

Oral complications and dental care in children with acute lymphoblastic leukaemia.

PubMed

Valéra, Marie-Cécile; Noirrit-Esclassan, Emmanuelle; Pasquet, Marléne; Vaysse, Fréderic

2015-08-01

Acute leukaemia is the most common type of childhood cancer, the acute lymphoblastic type accounting for the majority of cases. Children affected by leukaemia receive various forms of treatments including chemotherapeutic agents and stem cell transplants. Leukaemia and its treatment can directly or indirectly affect oral health and further dental treatments. The oral complications include mucositis, opportunistic infections, gingival inflammation and bleeding, xerostomia and carious lesions. An additional consideration in children is the impact of the treatments on the developing dentition and on orofacial growth. The aim of this review is to describe the oral complications in children with acute lymphoblastic leukaemia and the methods of prevention and management before, during and after the cancer treatment. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Potassium Channels Mediate Killing by Human Natural Killer Cells

NASA Astrophysics Data System (ADS)

Schlichter, Lyanne; Sidell, Neil; Hagiwara, Susumu

1986-01-01

Human natural killer (NK) cells in peripheral blood spontaneously recognize and kill a wide variety of target cells. It has been suggested that ion channels are involved in the killing process because there is a Ca-dependent stage and because killing by presensitized cytotoxic T lymphocytes, which in many respects resembles NK killing, is associated with changes in K and Na transport in the target cell. However, no direct evidence exists for ion channels in NK cells or in their target cells. Using the whole-cell variation of the patch-clamp technique, we found a voltage-dependent potassium (K+) current in NK cells. The K+ current was reduced in a dose-dependent manner by the K-channel blockers 4-aminopyridine and quinidine and by the traditional Ca-channel blockers verapamil and Cd2+. We tested the effects of ion-channel blockers on killing of two commonly used target cell lines: K562, which is derived from a human myeloid leukemia, and U937, which is derived from a human histiocytic leukemia. Killing of K562 target cells, determined in a standard 51Cr-release assay, was inhibited in a dose-dependent manner by verapamil, quinidine, Cd2+, and 4-aminopyridine at concentrations comparable to those that blocked the K+ current in NK cells. In K562 target cells only a voltage-dependent Na+ current was found and it was blocked by concentrations of tetrodotoxin that had no effect on killing. Killing of U937 target cells was also inhibited by the two ion-channel blockers tested, quinidine and verapamil. In this cell line only a small K+ current was found that was similar to the one in NK cells. We could not find any evidence of a Ca2+ current in target cells or in NK cells; therefore, our results cannot explain the Ca dependence of killing. Our findings show that there are K channels in NK cells and that these channels play a necessary role in the killing process. In contrast, the endogenous channel type in the target cell is probably not a factor in determining target cell sensitivity to natural killing.

Inotuzumab ozogamicin in the management of acute lymphoblastic leukaemia.

PubMed

Morley, N J; Marks, D I

2016-01-01

Whilst most adult patients with acute lymphoblastic leukaemia will go into remission with standard induction chemotherapy, many will relapse. Response rates to standard salvage chemotherapy regimens are low and the outlook on relapse is very poor and associated with significant morbidity and mortality hence the need for newer targeted approaches. Inotuzumab ozogamicin (previously known as CMC-544) is an antibody-drug conjugate and consists of a monoclonal anti-CD22 antibody bound to calicheamicin. The target, CD22, is widely expressed on acute lymphoblastic leukaemia cells making it a potential therapeutic target. The calicheamicin is delivered intracellularly and causes leukaemia cell apoptosis. Overall response rates of 57% were observed in a Phase II study and the final results of a Phase III randomised controlled trial comparing this drug to the investigator choice 'standard of care' chemotherapy are eagerly awaited. Whilst initial results are promising, there have been concerns regarding liver toxicity and the incidence of veno-occlusive disease of the liver especially in patients who have previously received or go on to allogeneic stem cell transplant.

[Prostatic localization revealing an acute myeloid leukemia. Apropos of a case].

PubMed

Smaoui, S; Lecomte, M J; Peraldi, R; Pernin, F

1998-09-01

The authors report an original case of acute myeloid leukaemia (AML) presenting in the form of acute urinary retention, confirmed by prostatic biopsy, with complete absence of any non-urological clinical features. Prostatic sites of leukaemia are frequent and classically reported, but often occur during the course of known leukaemia, and are rarely symptomatic, justifying biopsies in the presence of any prostatic symptoms. Immunolabelling represents the key to the diagnosis in the presence of undifferentiated cells demonstrated on prostatic biopsies. The outcome was fatal in this case, despite early chemotherapy. The clinical features, clinical course and therapeutic aspects of prostatic leukaemia are discussed.

Curcumin inhibits activation induced by urban particulate material or titanium dioxide nanoparticles in primary human endothelial cells

PubMed Central

Montiel-Dávalos, Angélica; Silva Sánchez, Guadalupe Jazmin; Huerta-García, Elizabeth; Rueda-Romero, Cristhiam; Soca Chafre, Giovanny; Mitre-Aguilar, Irma B.; Alfaro-Moreno, Ernesto; Pedraza-Chaverri, José

2017-01-01

Curcumin has protective effects against toxic agents and shows preventive properties for various diseases. Particulate material with an aerodynamic diameter of ≤10 μm (PM10) and titanium dioxide nanoparticles (TiO2-NPs) induce endothelial dysfunction and activation. We explored whether curcumin is able to attenuate different events related to endothelial activation. This includes adhesion, expression of adhesion molecules and oxidative stress induced by PM10 and TiO2-NPs. Human umbilical vein endothelial cells (HUVEC) were treated with 1, 10 and 100 μM curcumin for 1 h and then exposed to PM10 at 3 μg/cm2 or TiO2-NPs at 10 μg/cm2. Cell adhesion was evaluated by co-culture with U937 human myelomonocytic cells. Adhesion molecules expression was measured by flow cytometry after 3 or 24 h of exposure. Oxidative stress was determined by 2,7-dichlorodihydrofluorescein (H2DCF) oxidation. PM10 and TiO2-NPs induced the adhesion of U937 cells and the expression of E- and P-selectins, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1). The expression of E- and P-selectins matched the adhesion of monocytes to HUVEC after 3 h. In HUVEC treated with 1 or 10 μM curcumin, the expression of adhesion molecules and monocytes adhesion was significantly diminished. Curcumin also partially reduced the H2DCF oxidation induced by PM10 and TiO2-NPs. Our results suggest an anti-inflammatory and antioxidant role by curcumin attenuating the activation caused on endothelial cells by exposure to particles. Therefore, curcumin could be useful in the treatment of diseases where an inflammatory process and endothelial activation are involved. PMID:29244817

Three new aaptamine derivatives from the South China Sea sponge Aaptos aaptos.

PubMed

Gan, Jian-Hong; Hu, Wen-Zhen; Yu, Hao-Bing; Yang, Fan; Cao, Meng-Xue; Shi, Hua-Jin; Kang, Yong-Feng; Han, Bing-Nan

2015-01-01

Three new aaptamine derivatives (1-3), together with six known related compounds (4-9), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated on the basis of spectroscopic analyses. Compounds 1, 4, 5, 7, and 9 showed cytotoxic activities against HeLa, K562, MCF-7, and U937 cell lines with IC50 values in the range of 0.90-12.32 μM.

Sodium caseinate induces increased survival in leukaemic mouse J774 model.

PubMed

Córdova-Galaviz, Yolanda; Ledesma-Martínez, Edgar; Aguíñiga-Sánchez, Itzen; Soldevila-Melgarejo, Gloria; Soto-Cruz, Isabel; Weiss-Steider, Benny; Santiago-Osorio, Edelmiro

2014-01-01

Acute myeloid leukaemia is a neoplastic disease of haematopoietic stem cells. Although there have been recent advances regarding its treatment, mortality remains high. Consequently, therapeutic alternatives continue to be explored. In the present report, we present evidence that sodium caseinate (CasNa), a salt of the principal protein in milk, may possess important anti-leukaemic properties. J774 leukaemia macrophage-like cells were cultured with CasNa and proliferation, viability and differentiation were evaluated. These cells were also inoculated into BALB/c mice as a model of leukemia. We demonstrated that CasNa inhibits the in vitro proliferation and reduces viability of J774 cells, and leads to increased survival in vivo in a leukaemic mouse model. These data indicate that CasNa may be useful in leukaemia therapy. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Effect of Anacardium occidentale leaf extract on human acute lymphoblastic leukaemia cell lines.

PubMed

Santos, Janaína M; Cury, Nathalia M; Yunes, José A; López, Jorge A; Hernández-Macedo, Maria L

2018-01-16

Anacardium occidentale leaves are used in folk medicine due its therapeutic properties attributed to phenolic compounds. Therefore, this study was undertaken on its hydroethanolic leaf extract (AoHE) to evaluate cytotoxicity and apoptosis induction on acute lymphoblastic leukaemia cells. Results indicated that AoHE interfered in the cell cycle progression, inducing apoptosis by activation of casp3 at lower concentrations, thence, a promising candidate for the development of new cancer drugs.

Mycobacterium tuberculosis infection causes different levels of apoptosis and necrosis in human macrophages and alveolar epithelial cells.

PubMed

Danelishvili, Lia; McGarvey, Jeffery; Li, Yong-Jun; Bermudez, Luiz E

2003-09-01

Mycobacterium tuberculosis interacts with macrophages and epithelial cells in the alveolar space of the lung, where it is able to invade and replicate in both cell types. M. tuberculosis-associated cytotoxicity to these cells has been well documented, but the mechanisms of host cell death are not well understood. We examined the induction of apoptosis and necrosis of human macrophages (U937) and type II alveolar epithelial cells (A549) by virulent (H37Rv) and attenuated (H37Ra) M. tuberculosis strains. Apoptosis was determined by both enzyme-linked immunosorbent assay (ELISA) and TdT-mediated dUTP nick end labelling (TUNEL) assay, whereas necrosis was evaluated by the release of lactate dehydrogenase (LDH). Both virulent and attenuated M. tuberculosis induced apoptosis in macrophages; however, the attenuated strain resulted in significantly more apoptosis than the virulent strain after 5 days of infection. In contrast, cytotoxicity of alveolar cells was the result of necrosis, but not apoptosis. Although infection with M. tuberculosis strains resulted in apoptosis of 14% of the cells on the monolayer, cell death associated with necrosis was observed in 59% of alveolar epithelial cells after 5 days of infection. Infection with M. tuberculosis suppressed apoptosis of alveolar epithelial cells induced by the kinase inhibitor, staurosporine. Because our findings suggest that M. tuberculosis can modulate the apoptotic response of macrophages and epithelial cells, we carried out an apoptosis pathway-specific cDNA microarray analysis of human macrophages and alveolar epithelial cells. Whereas the inhibitors of apoptosis, bcl-2 and Rb, were upregulated over 2.5-fold in infected (48 h) alveolar epithelial cells, the proapoptotic genes, bad and bax, were downregulated. The opposite was observed when U937 macrophages were infected with M. tuberculosis. Upon infection of alveolar epithelial cells with M. tuberculosis, the generation of apoptosis, as determined by the expression of caspase-1, caspase-3 and caspase-10, was inhibited. Inhibition of replication of intracellular bacteria resulted in an increase in apoptosis in both cell types. Our results showed that the differential induction of apoptosis between macrophages and alveolar epithelial cells represents specific strategies of M. tuberculosis for survival in the host.

Staurosporine Induces Necroptotic Cell Death under Caspase-Compromised Conditions in U937 Cells

PubMed Central

Dunai, Zsuzsanna A.; Imre, Gergely; Barna, Gabor; Korcsmaros, Tamas; Petak, Istvan; Bauer, Pal I.; Mihalik, Rudolf

2012-01-01

For a long time necrosis was thought to be an uncontrolled process but evidences recently have revealed that necrosis can also occur in a regulated manner. Necroptosis, a type of programmed necrosis is defined as a death receptor-initiated process under caspase-compromised conditions. The process requires the kinase activity of receptor-interacting protein kinase 1 and 3 (RIPK1 and RIPK3) and mixed lineage kinase domain-like protein (MLKL), as a substrate of RIPK3. The further downstream events remain elusive. We applied known inhibitors to characterize the contributing enzymes in necroptosis and their effect on cell viability and different cellular functions were detected mainly by flow cytometry. Here we report that staurosporine, the classical inducer of intrinsic apoptotic pathway can induce necroptosis under caspase-compromised conditions in U937 cell line. This process could be hampered at least partially by the RIPK1 inhibitor necrotstin-1 and by the heat shock protein 90 kDa inhibitor geldanamycin. Moreover both the staurosporine-triggered and the classical death ligand-induced necroptotic pathway can be effectively arrested by a lysosomal enzyme inhibitor CA-074-OMe and the recently discovered MLKL inhibitor necrosulfonamide. We also confirmed that the enzymatic role of poly(ADP-ribose)polymerase (PARP) is dispensable in necroptosis but it contributes to membrane disruption in secondary necrosis. In conclusion, we identified a novel way of necroptosis induction that can facilitate our understanding of the molecular mechanisms of necroptosis. Our results shed light on alternative application of staurosporine, as a possible anticancer therapeutic agent. Furthermore, we showed that the CA-074-OMe has a target in the signaling pathway leading to necroptosis. Finally, we could differentiate necroptotic and secondary necrotic processes based on participation of PARP enzyme. PMID:22860037

Syk-dependent tyrosine phosphorylation of 3BP2 is required for optimal FcRγ-mediated phagocytosis and chemokine expression in U937 cells.

PubMed

Chihara, Kazuyasu; Kato, Yuji; Yoshiki, Hatsumi; Takeuchi, Kenji; Fujieda, Shigeharu; Sada, Kiyonao

2017-09-13

The adaptor protein c-Abl SH3 domain binding protein-2 (3BP2) is tyrosine phosphorylated by Syk in response to cross-linking of antigen receptors, which in turn activates various immune responses. Recently, a study using the mouse model of cherubism, a dominant inherited disorder caused by mutations in the gene encoding 3BP2, showed that 3BP2 is involved in the regulation of phagocytosis mediated by Fc receptor for IgG (FcγR) in macrophages. However, the molecular mechanisms underlying 3BP2-mediated regulation of phagocytosis and the physiological relevance of 3BP2 tyrosine phosphorylation remains elusive. In this study, we established various gene knockout U937 cell lines using the CRISPR/Cas9 system and found that 3BP2 is rapidly tyrosine phosphorylated by Syk in response to cross-linking of FcγRI. Depletion of 3BP2 caused significant reduction in the Fc receptor γ chain (FcRγ)-mediated phagocytosis in addition to the FcγRI-mediated induction of chemokine mRNA for IL-8, CCL3L3 and CCL4L2. Syk-dependent tyrosine phosphorylation of 3BP2 was required for overcoming these defects. Finally, we found that the PH and SH2 domains play important roles on FcγRI-mediated tyrosine phosphorylation of 3BP2 in HL-60 cells. Taken together, these results indicate that Syk-dependent tyrosine phosphorylation of 3BP2 is required for optimal FcRγ-mediated phagocytosis and chemokine expression.

A role for inflammatory mediators in heterologous desensitization of CysLT1 receptor in human monocytes

PubMed Central

Capra, Valérie; Accomazzo, Maria Rosa; Gardoni, Fabrizio; Barbieri, Silvia; Rovati, G. Enrico

2010-01-01

Cysteinyl-leukotrienes (cysteinyl-LT) are rapidly generated at sites of inflammation and, in addition to their role in asthma, rhinitis, and other immune disorders, are increasingly regarded as significant inflammatory factors in cancer, gastrointestinal, cardiovascular diseases. We recently demonstrated that in monocyte/macrophage–like U937 cells, extracellular nucleotides heterologously desensitize CysLT1 receptor (CysLT1R)-induced Ca2+ transients. Given that monocytes express a number of other inflammatory and chemoattractant receptors, this study was aimed at characterizing transregulation between these different stimuli. We demonstrate that in U937 cells and in primary human monocytes, a series of inflammatory mediators activating Gi-coupled receptor (FPR1, BLT1) desensitize CysLT1R-induced Ca2+ response unidirectionally through activation of PKC. Conversely, PAF-R, exclusively coupled to Gq, cross-desensitizes CysLT1R without the apparent involvement of any kinase. Interestingly, Gs-coupled receptors (β2AR, H1/2R, EP2/4R) are also able to desensitize CysLT1R response through activation of PKA. Heterologous desensitization seems to affect mostly the Gi-mediated signaling of the CysLT1R. The hierarchy of desensitization among agonists may be important for leukocyte signal processing at the site of inflammation. Considering that monocytes/macrophages are likely to be the major source of cysteinyl-LT in many immunological and inflammatory processes, shedding light on how their receptors are regulated will certainly help to better understand the role of these cells in orchestrating this complex network of integrated signals. PMID:19965602

ETV6-RUNX1 + Acute Lymphoblastic Leukaemia in Identical Twins.

PubMed

Ford, Anthony M; Greaves, Mel

2017-01-01

Acute leukaemia is the major subtype of paediatric cancer with a cumulative risk of 1 in 2000 for children up to the age of 15 years. Childhood acute lymphoblastic leukaemia (ALL) is a biologically and clinically diverse disease with distinctive subtypes; multiple chromosomal translocations exist within the subtypes and each carries its own prognostic relevance. The most common chromosome translocation observed is the t(12;21) that results in an in-frame fusion between the first five exons of ETV6 (TEL) and almost the entire coding region of RUNX1 (AML1).The natural history of childhood ALL is almost entirely clinically silent and is well advanced at the point of diagnosis. It has, however, been possible to backtrack this process through molecular analysis of appropriate clinical samples: (i) leukaemic clones in monozygotic twins that are either concordant or discordant for ALL; (ii) archived neonatal blood spots or Guthrie cards from individuals who later developed leukaemia; and (iii) stored, viable cord blood cells.Here, we outline our studies on the aetiology and pathology of childhood ALL that provide molecular evidence for a monoclonal, prenatal origin of ETV6-RUNX1+ leukaemia in monozygotic identical twins. We provide mechanistic support for the concept that altered patterns of infection during early childhood can deliver the necessary promotional drive for the progression of ETV6-RUNX1+ pre-leukaemic cells into a postnatal overt leukaemia.

ENL links histone acetylation to oncogenic gene expression in acute myeloid leukaemia.

PubMed

Wan, Liling; Wen, Hong; Li, Yuanyuan; Lyu, Jie; Xi, Yuanxin; Hoshii, Takayuki; Joseph, Julia K; Wang, Xiaolu; Loh, Yong-Hwee E; Erb, Michael A; Souza, Amanda L; Bradner, James E; Shen, Li; Li, Wei; Li, Haitao; Allis, C David; Armstrong, Scott A; Shi, Xiaobing

2017-03-09

Cancer cells are characterized by aberrant epigenetic landscapes and often exploit chromatin machinery to activate oncogenic gene expression programs. Recognition of modified histones by 'reader' proteins constitutes a key mechanism underlying these processes; therefore, targeting such pathways holds clinical promise, as exemplified by the development of bromodomain and extra-terminal (BET) inhibitors. We recently identified the YEATS domain as an acetyl-lysine-binding module, but its functional importance in human cancer remains unknown. Here we show that the YEATS domain-containing protein ENL, but not its paralogue AF9, is required for disease maintenance in acute myeloid leukaemia. CRISPR-Cas9-mediated depletion of ENL led to anti-leukaemic effects, including increased terminal myeloid differentiation and suppression of leukaemia growth in vitro and in vivo. Biochemical and crystal structural studies and chromatin-immunoprecipitation followed by sequencing analyses revealed that ENL binds to acetylated histone H3, and co-localizes with H3K27ac and H3K9ac on the promoters of actively transcribed genes that are essential for leukaemia. Disrupting the interaction between the YEATS domain and histone acetylation via structure-based mutagenesis reduced the recruitment of RNA polymerase II to ENL-target genes, leading to the suppression of oncogenic gene expression programs. Notably, disrupting the functionality of ENL further sensitized leukaemia cells to BET inhibitors. Together, our data identify ENL as a histone acetylation reader that regulates oncogenic transcriptional programs in acute myeloid leukaemia, and suggest that displacement of ENL from chromatin may be a promising epigenetic therapy, alone or in combination with BET inhibitors, for aggressive leukaemia.

Monoclonal antibody anti-MPO is useful in recognizing minimally differentiated acute myeloid leukaemia.

PubMed

Praxedes, M K; De Oliveira, L Z; Pereira, W da V; Quintana, I Z; Tabak, D G; De Oliveira, M S

1994-01-01

The enzyme myeloperoxidase (MPO) is the most specific marker of myeloid lineage. The recognition of acute myeloid leukaemia (AML) with minimally differentiation (AML-M0) is established with methods that include myeloid markers CD13/CD33 and detection of MPO in blast cells by immunological techniques or electron microscopy cytochemistry (EM). We have analysed the presence of MPO in leukaemic blast cells by conventional cytochemistry and immunological methods using a monoclonal antibody anti-MPO (CLB-MPO1) in 121 cases of acute leukaemia. The aim of the study was to investigate the sensitivity of this McAb to identify AML-M0, as CD13/CD33 can be expressed in some cases of acute lymphoblastic leukaemia (ALL) and EM cytochemistry is not always available in many laboratories. Anti-MPO was positive in all cases of AML (M1-M5) which were positive by Sudan Black B reaction in similar or higher percentage ratio for each case, although in some of them did not label with CD13/CD33 tested by IF and IPc techniques. Based on the anti-MPO positivity, 5 out of 10 cases called undifferentiated leukaemia (AUL) were reclassified as AML-M0, though 4 cases were CD13/CD33 negative. Furthermore, after analysing the anti-MPO expression among 32 cases of ALL, we had to reclassify four of them as acute biphenotypic leukaemia. We conclude that anti-MPO is a very sensitive and reliable tool in AML diagnosis and has an important role in distinguishing minimally differentiated AML and biphenotypic acute leukaemia from AUL and ALL.

Granulocytic sarcoma in a patient with chronic myeloid leukaemia in complete haematological, cytogenetic and molecular remission.

PubMed

Kittai, Adam; Yu, Eun-Mi; Tabbara, Imad

2014-12-23

Granulocytic sarcoma, also known as myeloid sarcoma, is an extramedullary tumour composed of immature myeloid cells. Granulocytic sarcoma is typically found in patients with acute myeloid leukaemia, accelerated phase or blast crisis of chronic myeloid leukaemia, myelodysplastic syndrome, or as an isolated event without bone marrow involvement. We present a case of granulocytic sarcoma in a patient with chronic myeloid leukaemia in the setting of complete haematological, molecular and cytogenetic remission. Our patient was first treated with imatinib for chronic-phase chronic myeloid leukaemia. After maintaining remission for 42 months, he developed a granulocytic sarcoma in his spine. In this case report, we describe our case, along with the three other cases reported in the literature. In addition to being a rare diagnosis, this case demonstrates the importance of being vigilant in diagnosing the cause of back pain and atypical symptoms in patients with a history of leukaemia. 2014 BMJ Publishing Group Ltd.

Versatility and nuances of the architecture of haematopoiesis - Implications for the nature of leukaemia.

PubMed

Brown, Geoffrey; Hughes, Philip J; Ceredig, Rhodri; Michell, Robert H

2012-01-01

For many years there was a widely accepted picture of how a haematopoietic stem cell (HSC) gives rise to the multiple types of blood and immune cells. This described the general nature of stem and progenitor cells and the pathways of cell development. Recent years have seen many attempts to re-draw the map of haematopoiesis. These have become increasingly complex, and they often envisage multiples routes to some cell types. The 'established' view that self-renewal in haematopoiesis only occurs in HSCs has been challenged by the recognition of self-renewing HSC-derived progenitor cells that display at least some fate restriction. This evolution of how normal haematopoiesis is viewed has inevitable implications for understanding the origins, disease progression and classification of the leukaemias. In essence, some progenitor cells are now seen as possessing a larger repertoire of routes to end-fates than was previously thought. This leads one to ask whether leukaemia stem cells are equally or less versatile than their normal counterparts? Copyright © 2011 Elsevier Ltd. All rights reserved.

Human serum amyloid A genes are expressed in monocyte/macrophage cell lines.

PubMed

Urieli-Shoval, S; Meek, R L; Hanson, R H; Eriksen, N; Benditt, E P

1994-09-01

Serum amyloid A (apoSAA) is a family of proteins found, mainly associated with high density lipoproteins, in the blood plasma of mammals and at least one avian species, the Pekin duck. These proteins are present in small amounts under normal circumstances, but their concentration is capable of rising 100- to 1,000-fold in situations involving tissue injury or infection. Like classic acute phase proteins they are produced in the liver; however, expression of one of the apoSAA genes is known to occur in activated macrophages of mice. We examined three human macrophage precursor cell lines (THP-1, U-937, and HL-60), before and after differentiation with phorbol 12-myristate 13-acetate or 1 alpha,25-dihydroxy-vitamin D3, for apoSAA messenger (m)-RNA expression and found that: 1) induction of steady-state apoSAA mRNA by lipopolysaccharide, interleukin-1, or interleukin-6 required the presence of the synthetic glucocorticoid dexamethasone; 2) the three known active genes, apoSAA1, apoSAA2, and apoSAA4, were induced in THP-1 cells, whereas the pseudogene apoSAA3 was not; 3) differentiated and undifferentiated THP-1 cells expressed apoSAA mRNA, but U-937 cells expressed apoSAA mRNA (low levels) only after phorbol 12-myristate 13-acetate differentiation and HL-60 cells did not express apoSAA mRNA whether differentiated or not; 4) apoSAA protein was detectable immunologically at a low level in lyophilized medium from induced THP-1 cells. Our findings are compatible with the hypotheses that 1) apoSAA gene expression in human monocytes/macrophages in vivo is differentiation dependent; 2) activated macrophages provide a local source of apoSAA at sites of tissue injury or inflammation; 3) apoSAA is induced in tissue macrophages by local stimuli, under conditions that may not evoke the systemic acute phase response.

Infection with human herpesvirus type 8 and human T-cell leukaemia virus type 1 among individuals participating in a case–control study in Havana City, Cuba

PubMed Central

Fernandez, L; Serraino, D; Rezza, G; Lence, J; Ortiz, R M; Cruz, T; Vaccarella, S; Sarmati, L; Andreoni, M; Franceschi, S

2002-01-01

Infection with human herpesvirus type 8 and with human T-cell leukaemia virus type-1 shows strong geographic variations. We conducted this study to assess prevalence and risk factors for human herpesvirus type 8 infection in Havana City, Cuba. Information and residual serum samples already collected for a hospital based case–control study were used. A total of 379 individuals (267 males and 112 females; median age=63 years) were evaluated. Antibodies to the lytic antigen of human herpesvirus type 8 were detected by using an immunofluorescence assay, while human T-cell leukaemia virus type-1 serology was performed by means of an ELISA test (alpha Biotech). Overall, 64 subjects (16.9%, 95% confidence interval: 13.1–20.0) were positive for human herpesvirus type 8 antibodies. Human herpesvirus type 8 seroprevalence significantly increased with age (odds ratio=1.9 for ⩾65 vs <55 years), and was twice as frequent in blacks than in whites. No association emerged with gender, socio-economic indicators, family size, history of sexually transmitted disease, sexual behaviour. Overall, 16 persons had anti-human T-cell leukaemia virus type-1 antibodies (4.2%, 95% confidence interval: 2.2–6.4). No relationship emerged between human T-cell leukaemia virus type-1 and human herpesvirus type 8 serostatus. The study findings indicate that human herpesvirus type 8 infection is relatively common in Havana City, Cuba, suggesting that Cuba may represent an intermediate endemical area. Sexual transmission does not seem to play a major role in the spread human herpesvirus type 8 infection. British Journal of Cancer (2002) 87, 1253–1256. doi:10.1038/sj.bjc.6600613 www.bjcancer.com © 2002 Cancer Research UK PMID:12439714

Severe asymptomatic hypophosphataemia in a child with T-acute lymphoblastic leukaemia.

PubMed

Zakaria, N H; Sthaneshwar, P; Shanmugam, H

2017-12-01

Hypophosphataemia is a metabolic disorder that is commonly encountered in critically ill patients. Phosphate has many roles in physiological functions, thus the depletion of serum phosphate could lead to impairment in multiple organ systems, which include the respiratory, cardiovascular, neurological and muscular systems and haematological and metabolic functions. Hypophosphataemia is defined as plasma phosphate level below 0.80 mmol per litre (mmol/L) and can be further divided into subgroups of mild (plasma phosphate of 0.66 to 0.79 mmol/L), moderate (plasma phosphate of 0.32 to 0.65 mmol/L) and severe (plasma phosphate of less than 0.32 mmol/L). The causes of hypophosphataemia include inadequate phosphate intake, decreased intestinal absorption, gastrointestinal or renal phosphate loss, and redistribution of phosphate into cells. Symptomatic hypophosphataemia associated with haematological malignancies has been reported infrequently. We report here a case of asymptomatic severe hypophosphataemia in a child with acute T-cell lymphoblastic leukaemia. A 14-year-old Chinese boy was diagnosed to have acute T cell lymphoblastic leukaemia (ALL). His serum biochemistry results were normal except inorganic phosphate and lactate dehydrogenase levels. The serum inorganic phosphate level was 0.1mmol/L and the level was low on repeated analysis. The child had no symptoms related to low phosphate levels. The possible causes of low phosphate were ruled out and urine Tmp/GFR was normal. Chemotherapy regime was started and the serum phosphate levels started to increase. Hypophosphataemia in leukaemia was attributed to shift of phosphorus into leukemic cells and excessive cellular phosphate consumption by rapidly proliferating cells. Several reports of symptomatic hypophosphataemia in myelogenous and lymphoblastic leukaemia in adults have been reported. To our knowledge this is the first case of severe asymptomatic hypophosphataemia in a child with ALL.

Development of an Integrated Chip for Automatic Tracking and Positioning Manipulation for Single Cell Lysis

PubMed Central

Young, Chao-Wang; Hsieh, Jia-Ling; Ay, Chyung

2012-01-01

This study adopted a microelectromechanical fabrication process to design a chip integrated with electroosmotic flow and dielectrophoresis force for single cell lysis. Human histiocytic lymphoma U937 cells were driven rapidly by electroosmotic flow and precisely moved to a specific area for cell lysis. By varying the frequency of AC power, 15 V AC at 1 MHz of frequency configuration achieved 100% cell lysing at the specific area. The integrated chip could successfully manipulate single cells to a specific position and lysis. The overall successful rate of cell tracking, positioning, and cell lysis is 80%. The average speed of cell driving was 17.74 μm/s. This technique will be developed for DNA extraction in biomolecular detection. It can simplify pre-treatment procedures for biotechnological analysis of samples. PMID:22736957

Development of an integrated chip for automatic tracking and positioning manipulation for single cell lysis.

PubMed

Young, Chao-Wang; Hsieh, Jia-Ling; Ay, Chyung

2012-01-01

This study adopted a microelectromechanical fabrication process to design a chip integrated with electroosmotic flow and dielectrophoresis force for single cell lysis. Human histiocytic lymphoma U937 cells were driven rapidly by electroosmotic flow and precisely moved to a specific area for cell lysis. By varying the frequency of AC power, 15 V AC at 1 MHz of frequency configuration achieved 100% cell lysing at the specific area. The integrated chip could successfully manipulate single cells to a specific position and lysis. The overall successful rate of cell tracking, positioning, and cell lysis is 80%. The average speed of cell driving was 17.74 μm/s. This technique will be developed for DNA extraction in biomolecular detection. It can simplify pre-treatment procedures for biotechnological analysis of samples.

Diagnosis of haematological disease using anti-i. II. Distinction between acute myeloblastic and acute lymphoblastic leukaemia.

PubMed

Shumak, K H; Rachkewich, R A; Beldotti, L E

1979-03-01

Leukaemic blast cells were obtained from the blood of six patients with acute lymphoblastic leukaemia (ALL) and 15 patients with acute myeloblastic leukaemia (AML). The blasts were compared with lymphocytes from normal subjects in cytotoxicity and 125I-labelled antibody binding tests using several examples of anti-i. As much i antigen was detected on ALL blasts as on normal lymphocytes; much less i antigen was detected on AML blasts. Studies of three patients with morphologically undifferentiated acute leukaemia suggest that, in tests with anti-i, blasts from such patients react either like lymphoblasts or myeloblasts despite the absence of the corresponding morphological features.

Oncogenic roles of PRL-3 in FLT3-ITD induced acute myeloid leukaemia

PubMed Central

Park, Jung Eun; Yuen, Hiu Fung; Zhou, Jian Biao; Al-aidaroos, Abdul Qader O; Guo, Ke; Valk, Peter J; Zhang, Shu Dong; Chng, Wee Joo; Hong, Cheng William; Mills, Ken; Zeng, Qi

2013-01-01

FLT3-ITD mutations are prevalent mutations in acute myeloid leukaemia (AML). PRL-3, a metastasis-associated phosphatase, is a downstream target of FLT3-ITD. This study investigates the regulation and function of PRL-3 in leukaemia cell lines and AML patients associated with FLT3-ITD mutations. PRL-3 expression is upregulated by the FLT3-STAT5 signalling pathway in leukaemia cells, leading an activation of AP-1 transcription factors via ERK and JNK pathways. PRL-3-depleted AML cells showed a significant decrease in cell growth. Clinically, high PRL-3 mRNA expression was associated with FLT3-ITD mutations in four independent AML datasets with 1158 patients. Multivariable Cox-regression analysis on our Cohort 1 with 221 patients identified PRL-3 as a novel prognostic marker independent of other clinical parameters. Kaplan–Meier analysis showed high PRL-3 mRNA expression was significantly associated with poorer survival among 491 patients with normal karyotype. Targeting PRL-3 reversed the oncogenic effects in FLT3-ITD AML models in vitro and in vivo. Herein, we suggest that PRL-3 could serve as a prognostic marker to predict poorer survival and as a promising novel therapeutic target for AML patients. PMID:23929599

Fusion of NUP98 and the SET binding protein 1 (SETBP1) gene in a paediatric acute T cell lymphoblastic leukaemia with t(11;18)(p15;q12).

PubMed

Panagopoulos, Ioannis; Kerndrup, Gitte; Carlsen, Niels; Strömbeck, Bodil; Isaksson, Margareth; Johansson, Bertil

2007-01-01

Three NUP98 chimaeras have previously been reported in T cell acute lymphoblastic leukaemia (T-ALL): NUP98/ADD3, NUP98/CCDC28A, and NUP98/RAP1GDS1. We report a T-ALL with t(11;18)(p15;q12) resulting in a novel NUP98 fusion. Fluorescent in situ hybridisation showed NUP98 and SET binding protein 1(SETBP1) fusion signals; other analyses showed that exon 12 of NUP98 was fused in-frame with exon 5 of SETBP1. Nested polymerase chain reaction did not amplify the reciprocal SETBP1/NUP98, suggesting that NUP98/SETBP1 transcript is pathogenetically important. SETBP1 has previously not been implicated in leukaemias; however, it encodes a protein that specifically interacts with SET, fused to NUP214 in a case of acute undifferentiated leukaemia.

Fallout, radiation doses near Dounreay, and childhood leukaemia.

PubMed Central

Darby, S C; Doll, R

1987-01-01

Possible explanations for the recently reported increased incidence of childhood leukaemia around Dounreay were examined in the light of changes in the national incidence of leukaemia that occurred during the period of exposure to fallout from international testing of nuclear weapons in the atmosphere. It was concluded that the increase could not be accounted for by an underestimate of the risk of leukaemia per unit dose of radiation at low doses and low dose rates, nor by an underestimate of the relative biological efficiency of high as compared with low linear energy transfer radiation. One possible explanation was underestimation of doses to the red bone marrow due to the discharges at Dounreay relative to the dose from fallout, though investigation of ways in which this might have occurred did not suggest anything definite. Other possible explanations included a misconception of the site of origin of childhood leukaemia, outbreaks of an infectious disease, and exposure to some other, unidentified environmental agent. These findings weigh heavily against the hypothesis that the recent increase in childhood leukaemia near Dounreay might be accounted for by radioactive discharges from nuclear plants, unless the doses to the stem cells from which childhood leukaemia originates have been grossly underestimated. PMID:3103820

IL-8 as mediator in the microenvironment-leukaemia network in acute myeloid leukaemia.

PubMed

Kuett, Alexander; Rieger, Christina; Perathoner, Deborah; Herold, Tobias; Wagner, Michaela; Sironi, Silvia; Sotlar, Karl; Horny, Hans-Peter; Deniffel, Christian; Drolle, Heidrun; Fiegl, Michael

2015-12-17

The bone marrow microenvironment is physiologically hypoxic with areas being as low as 1% O2, e.g. the stem cell niche. Acute myeloid leukaemia (AML) blasts misuse these bone marrow niches for protection by the local microenvironment, but also might create their own microenvironment. Here we identify IL-8 as a hypoxia-regulated cytokine in both AML cell lines and primary AML samples that is induced within 48 hours of severe hypoxia (1% O2). IL-8 lacked effects on AML cells but induced migration in mesenchymal stromal cells (MSC), an integral part of the bone marrow. Accordingly, MSC were significantly increased in AML bone marrow as compared to healthy bone marrow. Interestingly, mononuclear cells obtained from healthy bone marrow displayed both significantly lower endogenous and hypoxia-induced production of IL-8. IL-8 mRNA expression in AML blasts from 533 patients differed between genetic subgroups with significantly lower expression of IL-8 in acute promyelocytic leukaemia (APL), while in non APL-AML patients with FLT ITD had the highest IL-8 expression. In this subgroup, high IL-8 expression was also prognostically unfavourable. In conclusion, hypoxia as encountered in the bone marrow specifically increases IL-8 expression of AML, which in turn impacts niche formation. High IL-8 expression might be correlated with poor prognosis in certain AML subsets.

The Anti-cancer Activity of Vernonia divaricata Sw against Leukaemia, Breast and Prostate Cancers In Vitro

PubMed Central

Lowe, HIC; Daley-Beckford, D; Toyang, NJ; Watson, C; Hartley, S; Bryant, J

2014-01-01

Background: Vernonia divaricata is one of five endemic Vernonia species of Jamaica. The ethnomedicinal uses of other species have been established, however, scientific validation of this species has not yet been done and as such this paper is aimed at identifying the anti-cancer activity of V divaricata against leukaemia, breast and prostate cancer cell lines. Methods: Leaves and stems of V divaricata were dried and milled into powder. The crude hexane and methanol extracts of the leaves and stems were obtained and bio-assayed using WST-1 cell proliferation assay against leukaemia, breast and prostate cancer cell lines. Results: The crude hexane and methanol extracts of V divaricata were able to significantly retard the growth of the MCF-7 (breast), HL-60 (leukaemia) and the PC-3 (prostate) cancer cell lines. The crude methanol extract of the stem was the strongest, exhibiting anti-proliferation activity with IC50 values of 10.14, 12.63 and 9.894 μg/ml for the HL-60, MCF-7 and PC-3 cancer cell lines, respectively, with the most potent toward prostate cancer. Conclusion: The medicinal use of V divaricata as an anti-cancer agent was corroborated as the crude hexane and methanol extracts demonstrated potent anti-proliferation activity and as such hold potential for further research and development into a drug to prevent or treat various cancers. PMID:25429469

Computer-Aided Diagnosis of Acute Lymphoblastic Leukaemia

PubMed Central

2018-01-01

Leukaemia is a form of blood cancer which affects the white blood cells and damages the bone marrow. Usually complete blood count (CBC) and bone marrow aspiration are used to diagnose the acute lymphoblastic leukaemia. It can be a fatal disease if not diagnosed at the earlier stage. In practice, manual microscopic evaluation of stained sample slide is used for diagnosis of leukaemia. But manual diagnostic methods are time-consuming, less accurate, and prone to errors due to various human factors like stress, fatigue, and so forth. Therefore, different automated systems have been proposed to wrestle the glitches in the manual diagnostic methods. In recent past, some computer-aided leukaemia diagnosis methods are presented. These automated systems are fast, reliable, and accurate as compared to manual diagnosis methods. This paper presents review of computer-aided diagnosis systems regarding their methodologies that include enhancement, segmentation, feature extraction, classification, and accuracy. PMID:29681996

Leukaemia cutis after starting bendamustine: cause or coincidence?

PubMed

Mawri, Sagger; Nabi, Shahzaib; Jallad, Bassel; Won, Joseph

2015-09-21

A 55-year-old man with a history of chronic lymphocytic leukaemia presented with diffuse skin lesions that began 1 week after starting a new chemotherapy regimen with bendamustine and rituximab. The lesions appeared as erythematous papules that were neither itchy nor tender, and did not blanch with pressure. Initially, they began on his scalp and flanks and, over the next few days, spread diffusely throughout his body, becoming darker in colour. Skin biopsy showed atypical clonal B-cell proliferation in a perivascular, periadnexal and dermal band-like distribution, which was further characterised by immunohistochemical evaluation. These findings were suggestive of leukaemia cutis and consistent with the patient's chronic lymphocytic leukaemia, which was previously confirmed by bone marrow biopsy. The bendamustine was stopped and the patient's chemotherapy regimen was switched to fludarabine, cyclophosphamide and rituximab. Shortly thereafter, the leukaemia cutis regressed significantly. 2015 BMJ Publishing Group Ltd.

Chemical exposure and infant leukaemia: development of an adverse outcome pathway (AOP) for aetiology and risk assessment research.

PubMed

Pelkonen, Olavi; Terron, Andrea; Hernandez, Antonio F; Menendez, Pablo; Bennekou, Susanne Hougaard

2017-08-01

Infant leukaemia (<1 year old) is a rare disease of an in utero origin at an early phase of foetal development. Rearrangements of the mixed-lineage leukaemia (MLL) gene producing abnormal fusion proteins are the most frequent genetic/molecular findings in infant B cell-acute lymphoblastic leukaemia. In small epidemiological studies, mother/foetus exposures to some chemicals including pesticides have been associated with infant leukaemia; however, the strength of evidence and power of these studies are weak at best. Experimental in vitro or in vivo models do not sufficiently recapitulate the human disease and regulatory toxicology studies are unlikely to capture this kind of hazard. Here, we develop an adverse outcome pathway (AOP) based substantially on an analogous disease-secondary acute leukaemia caused by the topoisomerase II (topo II) poison etoposide-and on cellular and animal models. The hallmark of the AOP is the formation of MLL gene rearrangements via topo II poisoning, leading to fusion genes and ultimately acute leukaemia by global (epi)genetic dysregulation. The AOP condenses molecular, pathological, regulatory and clinical knowledge in a pragmatic, transparent and weight of evidence-based framework. This facilitates the interpretation and integration of epidemiological studies in the process of risk assessment by defining the biologically plausible causative mechanism(s). The AOP identified important gaps in the knowledge relevant to aetiology and risk assessment, including the specific embryonic target cell during the short and spatially restricted period of susceptibility, and the role of (epi)genetic features modifying the initiation and progression of the disease. Furthermore, the suggested AOP informs on a potential Integrated Approach to Testing and Assessment to address the risk caused by environmental chemicals in the future.

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

PubMed

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

2017-12-01

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

Cancer progression by reprogrammed BCAA metabolism in myeloid leukaemia.

PubMed

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

2017-05-25

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

Anti-leukaemic activity of a novel haploidentical-transplantation approach employing unmanipulated bone marrow followed by CD6-depleted peripheral blood stem cells in children with refractory/relapsed acute leukaemia.

PubMed

Schuster, Friedhelm R; Meisel, Roland; Führer, Monika; Reuther, Susanne; Hauer, Julia; Tischer, Johanna; Feuchtinger, Tobias; Laws, Hans-Jürgen; Kolb, Hans-Jochem; Borkhardt, Arndt

2013-09-01

The treatment outcome of children with refractory acute leukaemia or relapse post-stem cell transplantation is dismal. We report 10 children (non-remission n = 7) who underwent a new haploidentical transplant approach utilizing unmanipulated bone marrow followed by CD6-depleted peripheral blood stem cells. Nine patients had successful engraftment and no evidence of leukaemia. Acute and chronic graft-versus-host-disease was observed in five and three patients, respectively; two patients died of treatment-related toxicity. Seven patients relapsed after 7 (range 3-34) months, however two patients are alive at 6·5 and 7·0 years. This approach provides anti-leukaemic activity even in heavily pre-treated children but long-term disease control requires further intervention. © 2013 John Wiley & Sons Ltd.

A case of hypotriploid chromosome in a patient with acute lymphoblastic leukaemia.

PubMed

Khan, Bilal Ahmed; Ali Baig, Mirza Faris; Siddiqui, Nadir

2017-11-01

TA 58-61, XXXX, hypotriploid chromosome was detected in the cytogenetics report of a 28 years old female patient, known case of B-cell Acute Lymphoblastic Leukaemia. On admission, the patient had normal physical examination findings and mental status, except history of fever spikes and generalized bone pains. The patient was admitted for induction of chemotherapy. Bone Marrow/Trephine biopsy report showed diffuse infiltration with blast cells with overall cellularity around 80-85% and suppressed normal haematopoiesis. Hypotriploid chromosome number in patients with B-cell Acute Lymphoblastic Leukaemia is a unique finding which, according to WHO classification of ALL, is an important prognostic factor itself and these cases have a favourable prognosis. There are only a few medical reports published about cases with similar presentations in Pakistan. Therefore, this case is very unique and further work should be done for better understanding of similar presentations and to find out more about its epidemiology.

Application of a haematopoetic progenitor cell-targeted adeno-associated viral (AAV) vector established by selection of an AAV random peptide library on a leukaemia cell line

PubMed Central

Stiefelhagen, Marius; Sellner, Leopold; Kleinschmidt, Jürgen A; Jauch, Anna; Laufs, Stephanie; Wenz, Frederik; Zeller, W Jens; Fruehauf, Stefan; Veldwijk, Marlon R

2008-01-01

Background For many promising target cells (e.g.: haematopoeitic progenitors), the susceptibility to standard adeno-associated viral (AAV) vectors is low. Advancements in vector development now allows the generation of target cell-selected AAV capsid mutants. Methods To determine its suitability, the method was applied on a chronic myelogenous leukaemia (CML) cell line (K562) to obtain a CML-targeted vector and the resulting vectors tested on leukaemia, non-leukaemia, primary human CML and CD34+ peripheral blood progenitor cells (PBPC); standard AAV2 and a random capsid mutant vector served as controls. Results Transduction of CML (BV173, EM3, K562 and Lama84) and AML (HL60 and KG1a) cell lines with the capsid mutants resulted in an up to 36-fold increase in CML transduction efficiency (K562: 2-fold, 60% ± 2% green fluorescent protein (GFP)+ cells; BV173: 9-fold, 37% ± 2% GFP+ cells; Lama84: 36-fold, 29% ± 2% GFP+ cells) compared to controls. For AML (KG1a, HL60) and one CML cell line (EM3), no significant transduction (<1% GFP+ cells) was observed for any vector. Although the capsid mutant clone was established on a cell line, proof-of-principle experiments using primary human cells were performed. For CML (3.2-fold, mutant: 1.75% ± 0.45% GFP+ cells, p = 0.03) and PBPC (3.5-fold, mutant: 4.21% ± 3.40% GFP+ cells) a moderate increase in gene transfer of the capsid mutant compared to control vectors was observed. Conclusion Using an AAV random peptide library on a CML cell line, we were able to generate a capsid mutant, which transduced CML cell lines and primary human haematopoietic progenitor cells with higher efficiency than standard recombinant AAV vectors. PMID:18789140

Lysosomotropic cationic drugs induce cytostatic and cytotoxic effects: Role of liposolubility and autophagic flux and antagonism by cholesterol ablation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parks, Alexandre; Marceau, François, E-mail: franc

Cation trapping in acidic cell compartments determines an antiproliferative effect that has a potential interest in oncology, as shown by clinical data and trials involving chloroquine and hydroxychloroquine. To further characterize the mechanism of this effect, we studied a series of 6 substituted triethylamine (s-Et{sub 3}N) drugs that encompasses a wide range of liposolubility (amiodarone, quinacrine, chloroquine, hydroxychloroquine, lidocaine, and procainamide). Three tumor cell lines and primary human endothelial cells were exploited in proliferation assays (48 h, cell counts). Accumulation of the autophagic effector LC3 II and the apoptotic marker cleaved PARP1 (immunoblots), cytotoxicity, cell cycle analysis and endocytic functionmore » were further tested in the p53-null histiocytic lymphoma U937 line. A profound and desynchronized antiproliferative effect was observed in response to all s-Et{sub 3}Ns with essentially no cell type specificity. Predictors of s-Et{sub 3}N potency were liposolubility and the acute accumulation of the autophagic effector LC3 II (6 h-treatments). For each s-Et{sub 3}N, there was an antiproliferative concentration range where cytotoxicity and apoptosis were not triggered in U937 cells (24–48 h-treatments). Quinacrine was the most potent cytostatic drug (1–5 μM). Co-treatment of cells with inhibitors of cholesterol, β-cyclodextrin or lovastatin, partially reversed the antiproliferative effect of each s-Et{sub 3}N. The cytopathology induced by cationic drug accumulation includes a cytostatic effect. Its intensity is cell type- and p53-independent, but predicted by the inhibition of autophagic flux and by the liposolubility of individual drugs and alleviated by cholesterol ablation. The superiority of quinacrine, biomarker value of LC3 II and antagonism by a statin may be clinically relevant. - Highlights: • Cation trapping in acidic cell compartments induces a cytostatic effect. • A series of substituted triethylamines has been studied in 4 cell types. • Cytostatic potency is predicted by lipophilicity and autophagic flux inhibition. • β-Cyclodextrin or lovastatin co-treatment reverses the antiproliferative effect.« less

Phosphorylation of STAT-1 Serine 727 Is Prolonged in HLA-B27-Expressing Human Monocytic Cells

PubMed Central

Ruuska, Marja; Sahlberg, Anna S.; Granfors, Kaisa; Penttinen, Markus A.

2013-01-01

A tissue antigen, HLA-B27, is strongly associated with a group of rheumatic diseases called spondyloarthritides. Despite the intensive research, the exact role of HLA-B27 in the pathogenesis of these diseases is still unclear. Here we studied whether HLA-B27 modulates the phosphorylation of signal transducer and activator of transcription 1 (STAT-1) serine 727 residue and the localization of STAT-1 in Salmonella-infected human monocytic cells. In addition, we studied the role of signaling molecule double-stranded RNA activated protein kinase (PKR) in these modulatory effects. U937 human monocytic cell transfectants stably expressing wild type HLA-B27 or mutated HLA-B27 heavy chains with amino acid substitutions in the B pocket were prepared. The PMA-differentiated cells were infected with S. enteritidis. Western blotting was used to detect the phosphorylation of STAT-1, and to visualize the localization of STAT-1 in the cells confocal microscopy was used. Specific inhibitors were employed to study the role of PKR in STAT-1 phosphorylation. We discovered that the phosphorylation of STAT-1 serine 727 is prolonged in cells expressing misfolding forms of HLA-B27 after S. enteritidis infection, whereas in mock cells and in cells expressing mutated, non-misfolding HLA-B27 the phosphorylation of serine 727 is transient. Interestingly, STAT-1 serine 727 phosphorylation is partly dependent on PKR. In addition, more STAT-1 is localized in the nucleus of HLA-B27-expressing cells, even before an external trigger, when compared to mock cells. In conclusion, our results show that the phosphorylation of STAT-1 serine 727 residue is prolonged in HLA-B27-expressing monocyte-macrophage U937 cells after bacterial infection. This is of interest since the phosphorylation of serine 727 on STAT-1 is suggested to contribute to macrophage activation and promote inflammatory responses. Therefore, our results provide a mechanism which explains how the expression of an HLA-B27 molecule can impact the course of Salmonella infection and reactive arthritis. PMID:23349666

The subclonal complexity of STIL-TAL1+ T-cell acute lymphoblastic leukaemia.

PubMed

Furness, Caroline L; Mansur, Marcela B; Weston, Victoria J; Ermini, Luca; van Delft, Frederik W; Jenkinson, Sarah; Gale, Rosemary; Harrison, Christine J; Pombo-de-Oliveira, Maria S; Sanchez-Martin, Marta; Ferrando, Adolfo A; Kearns, Pamela; Titley, Ian; Ford, Anthony M; Potter, Nicola E; Greaves, Mel

2018-03-20

Single-cell genetics were used to interrogate clonal complexity and the sequence of mutational events in STIL-TAL1+ T-ALL. Single-cell multicolour FISH was used to demonstrate that the earliest detectable leukaemia subclone contained the STIL-TAL1 fusion and copy number loss of 9p21.3 (CDKN2A/CDKN2B locus), with other copy number alterations including loss of PTEN occurring as secondary subclonal events. In three cases, multiplex qPCR and phylogenetic analysis were used to produce branching evolutionary trees recapitulating the snapshot history of T-ALL evolution in this leukaemia subtype, which confirmed that mutations in key T-ALL drivers, including NOTCH1 and PTEN, were subclonal and reiterative in distinct subclones. Xenografting confirmed that self-renewing or propagating cells were genetically diverse. These data suggest that the STIL-TAL1 fusion is a likely founder or truncal event. Therapies targeting the TAL1 auto-regulatory complex are worthy of further investigation in T-ALL.

Senescence-associated reprogramming promotes cancer stemness.

PubMed

Milanovic, Maja; Fan, Dorothy N Y; Belenki, Dimitri; Däbritz, J Henry M; Zhao, Zhen; Yu, Yong; Dörr, Jan R; Dimitrova, Lora; Lenze, Dido; Monteiro Barbosa, Ines A; Mendoza-Parra, Marco A; Kanashova, Tamara; Metzner, Marlen; Pardon, Katharina; Reimann, Maurice; Trumpp, Andreas; Dörken, Bernd; Zuber, Johannes; Gronemeyer, Hinrich; Hummel, Michael; Dittmar, Gunnar; Lee, Soyoung; Schmitt, Clemens A

2018-01-04

Cellular senescence is a stress-responsive cell-cycle arrest program that terminates the further expansion of (pre-)malignant cells. Key signalling components of the senescence machinery, such as p16 INK4a , p21 CIP1 and p53, as well as trimethylation of lysine 9 at histone H3 (H3K9me3), also operate as critical regulators of stem-cell functions (which are collectively termed 'stemness'). In cancer cells, a gain of stemness may have profound implications for tumour aggressiveness and clinical outcome. Here we investigated whether chemotherapy-induced senescence could change stem-cell-related properties of malignant cells. Gene expression and functional analyses comparing senescent and non-senescent B-cell lymphomas from Eμ-Myc transgenic mice revealed substantial upregulation of an adult tissue stem-cell signature, activated Wnt signalling, and distinct stem-cell markers in senescence. Using genetically switchable models of senescence targeting H3K9me3 or p53 to mimic spontaneous escape from the arrested condition, we found that cells released from senescence re-entered the cell cycle with strongly enhanced and Wnt-dependent clonogenic growth potential compared to virtually identical populations that had been equally exposed to chemotherapy but had never been senescent. In vivo, these previously senescent cells presented with a much higher tumour initiation potential. Notably, the temporary enforcement of senescence in p53-regulatable models of acute lymphoblastic leukaemia and acute myeloid leukaemia was found to reprogram non-stem bulk leukaemia cells into self-renewing, leukaemia-initiating stem cells. Our data, which are further supported by consistent results in human cancer cell lines and primary samples of human haematological malignancies, reveal that senescence-associated stemness is an unexpected, cell-autonomous feature that exerts its detrimental, highly aggressive growth potential upon escape from cell-cycle blockade, and is enriched in relapse tumours. These findings have profound implications for cancer therapy, and provide new mechanistic insights into the plasticity of cancer cells.

Identification of early B cell precursors (stage 1 and 2 hematogones) in the peripheral blood.

PubMed

Kurzer, Jason H; Weinberg, Olga K

2018-05-25

Differentiating malignant B-lymphoblasts from early benign B cell precursors (hematogones) is a vital component of the diagnosis of B-lymphoblastic leukaemia. It has been previously reported that only late-stage B cell precursors circulate in the peripheral blood. Consequently, flow cytometric detection of cells with immunophenotypic findings similar to earlier stage precursors in the peripheral blood justifiably raises concern for involvement by B-lymphoblastic leukaemia. We report here, however, that benign early B cell precursors can indeed be detected in the peripheral blood, thus complicating the interpretation of flow cytometric findings derived from these sample types. A retrospective search of our collective databases identified 13 cases containing circulating early stage B cell precursors. The patients ranged in age from 15 days to 85 years old. All positive cases demonstrated that the earlier B cell precursors were associated with later stage precursors, a finding that could help differentiate these cells from B-lymphoblastic leukaemia. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Acute undifferentiated leukaemia in a dog.

PubMed

Miglio, A; Antognoni, M T; Miniscalco, B; Caivano, D; Lepri, E; Birettoni, F; Mangili, V

2014-12-01

Acute undifferentiated leukaemia (AUL) is considered a separate entity in the context of acute leukaemias. AUL is extremely rare in both humans and dogs, has a rapid clinical course and does not respond to treatment. It is characterised by the presence of blast cells within the bone marrow and/or peripheral blood at levels ≥ 20% and even up to 100% of all nucleated cells. Blast cells are unable to be differentiated on morphological, cytochemical and phenotypic criteria into myeloid or lymphoid lineages because of their immaturity and/or atypia. An 8-year-old German Shepherd dog was referred for depression, asthenia, mild anaemia, thrombocytopenia and marked leucocytosis. Abdominal ultrasound showed hepatomegaly, splenomegaly, bilateral nephromegaly and enlargement of mesenteric lymph nodes. Echocardiography revealed biventricular hypertrophy with abnormal tissue density of the myocardium. Blood and bone marrow smears were composed of 95% unclassifiable and/or atypical blast cells and signs of dysplasia of the erythroid and thrombocytic/megakaryocytic lineages were present. Blast cells were negative for all cytochemical stains used and flow cytometry of peripheral blood revealed 85% of total leucocytes consisting of small-to-medium-sized cells, negative for all lymphoid and myeloid markers except CD45 and CD34. After necropsy, cytology and histology revealed that blast cells had diffusely infiltrated all tissues examined. Both erythroid and megakaryocytic extramedullary haemopoiesis was also detected in the spleen, lymph nodes and liver. All immunohistochemical stains used were negative. On the basis of all the results, a diagnosis of acute leukaemia involving a very primitive haematopoietic precursor was made. © 2014 Australian Veterinary Association.

Glucocorticoid sensitisation in Mixed Lineage Leukaemia-rearranged acute lymphoblastic leukaemia by the pan-BCL-2 family inhibitors gossypol and AT-101.

PubMed

Spijkers-Hagelstein, Jill A P; Schneider, Pauline; Pinhanços, Sandra Mimoso; Garrido Castro, Patricia; Pieters, Rob; Stam, Ronald W

2014-06-01

Resistance to glucocorticoids (GCs) remains a major problem in the treatment of infants with acute lymphoblastic leukaemia (ALL) carrying Mixed Lineage Leukaemia (MLL) translocations. Despite intensive research, the mechanism(s) underlying GC resistance remain poorly understood. Recent studies suggested an important role for the pro-survival BCL-2 family member MCL1 in GC resistance in MLL-rearranged ALL. We exposed GC-resistant MLL-rearranged SEMK2 cells to potent MCL1-inhibiting agents, including gossypol, AT-101, rapamycin, SU9516 and obatoclax (GX15-070) and determined GC sensitisation using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays. Using Western blotting we analysed the protein expression of most BCL-2 family members in MLL-rearranged SEMK2 cells after treatment with potent MCL-1 inhibiting agents. Only gossypol and its synthetic analogue AT-101 induced GC sensitivity in MLL-rearranged ALL cells. Remarkably, the GC-sensitising effects of gossypol and AT-101 appeared not to be mediated by down-regulation MCL1 or other anti-apoptotic BCL-2 family members, but rather involved up-regulation of multiple pro-apoptotic BCL-2 family members, in particular that of BIM and BID. In conclusion, gossypol and AT-101 induce GC sensitivity in MLL-rearranged ALL cells, most likely mediated by the activation of BID and BIM without the necessity to down-regulate anti-apoptotic BCL-2 family members like MCL1. Hence, co-administration of either gossypol or AT-101 during GC treatment of GC-resistant MLL-rearranged ALL patients may overcome GC resistance and improve prognosis in this high-risk childhood leukaemia. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structure–Activity Relationship Studies and in Vivo Activity of Guanidine-Based Sphingosine Kinase Inhibitors: Discovery of SphK1- and SphK2-Selective Inhibitors

PubMed Central

Kharel, Yugesh; Raje, Mithun R.; Gao, Ming; Tomsig, Jose L.; Lynch, Kevin R.; Santos, Webster L.

2015-01-01

Sphingosine 1-phosphate (S1P) is a pleiotropic signaling molecule that acts as a ligand for five G-protein coupled receptors (S1P1–5) whose downstream effects are implicated in a variety of important pathologies including sickle cell disease, cancer, inflammation, and fibrosis. The synthesis of S1P is catalyzed by sphingosine kinase (SphK) isoforms 1 and 2, and hence, inhibitors of this phosphorylation step are pivotal in understanding the physiological functions of SphKs. To date, SphK1 and 2 inhibitors with the potency, selectivity, and in vivo stability necessary to determine the potential of these kinases as therapeutic targets are lacking. Herein, we report the design, synthesis, and structure–activity relationship studies of guanidine-based SphK inhibitors bearing an oxadiazole ring in the scaffold. Our studies demonstrate that SLP120701, a SphK2-selective inhibitor (Ki = 1 μM), decreases S1P levels in histiocytic lymphoma (U937) cells. Surprisingly, homologation with a single methylene unit between the oxadiazole and heterocyclic ring afforded a SphK1-selective inhibitor in SLP7111228 (Ki = 48 nM), which also decreased S1P levels in cultured U937 cells. In vivo application of both compounds, however, resulted in contrasting effect in circulating levels of S1P. Administration of SLP7111228 depressed blood S1P levels while SLP120701 increased levels of S1P. Taken together, these compounds provide an in vivo chemical toolkit to interrogate the effect of increasing or decreasing S1P levels and whether such a maneuver can have implications in disease states. PMID:25643074

Pirfenidone exerts a suppressive effect on CCL18 expression in U937-derived macrophages partly by inhibiting STAT6 phosphorylation.

PubMed

Saito, Yoshinobu; Azuma, Arata; Matsuda, Kuniko; Kamio, Koichiro; Abe, Shinji; Gemma, Akihiko

2016-10-27

CC chemokine ligand 18 (CCL18) is suggested to play a role in the development of pulmonary fibrosis. Macrophages are thought to be the main source of CCL18, and the effect of pirfenidone, an anti-fibrotic agent for idiopathic pulmonary fibrosis, on the expression of CCL18 in macrophages warrants investigation. The purpose of this study was to investigate the effect of pirfenidone on the expression of CCL18 in macrophages. U937 cells were differentiated into macrophages by phorbol myristate acetate and then stimulated with recombinant IL-4 to induce the production of CCL18. The cells were treated with pirfenidone, and the mRNA and protein levels for CCL18 were measured by a reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The effects of pirfenidone on the IL-4 receptor (IL-4R) expression and STAT6 activation were investigated and on the JAK kinase activity were measured using the Z'-LYTE™ kinase assay. Pirfenidone significantly suppressed the expression of CCL18 when the cells were treated with concentrations of 50-250 μg/mL. Pirfenidone did not affect the expression of the IL-4R components. The selective STAT6 inhibitor AS1517499 suppressed CCL18 expression. Both AS1517499 and pirfenidone suppressed STAT6 phosphorylation (p < .05), although the effect of pirfenidone was less marked than that of AS1517499. The Z'-LYTE™ kinase assay showed a reduction in the activities of JAK1, JAK3 and TYK2 by pirfenidone. Pirfenidone suppresses CCL18 expression in macrophages and this effect is thought to be attributed partly to the inhibition of STAT6 phosphorylation.

EFFECT OF A PLURONIC® P123 FORMULATION ON THE NITRIC OXIDE-GENERATING DRUG JS-K

PubMed Central

Kaur, Imit; Kosak, Ken M.; Terrazas, Moises; Herron, James N.; Kern, Steven E.; Boucher, Kenneth M.; Shami, Paul J.

2014-01-01

Purpose O2-(2,4-dinitrophenyl)1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate] or JS-K is a nitric oxide-producing prodrug of the arylated diazeniumdiolate class with promising anti-tumor activity. JS-K has challenging solubility and stability properties. We aimed to characterize and compare Pluronic® P123-formulated JS-K (P123/JS-K) with free JS-K. Methods We determined micelle size, shape, and critical micelle concentration of Pluronic® P123. Efficacy was evaluated in vitro using HL-60 and U937 cells and in vivo in a xenog raft in NOD/SCID IL2Rγnull mice using HL-60 cells. We compared JS-K and P123/JS-K stability in different media. We also compared plasma protein binding of JS-K and P123/JS-K. We determined the binding and Stern Volmer constants, and thermodynamic parameters. Results Spherical P123/JS-K micelles were smaller than blank P123. P123/JS-K formulation was more stable in buffered saline, whole blood, plasma and RPMI media as compared to free JS-K. P123 affected the protein binding properties of JS-K. In vitro it was as efficacious as JS-K alone when tested in HL-60 and U937 cells and in vivo greater tumor regression was observed for P123/JS-K treated NOD/SCID IL2Rγnull mice when compared to free JS-K-treated NOD/SCID IL2Rγnull mice. Conclusions Pluronic® P123 solubilizes, stabilizes and affects the protein binding characteristics of JS-K. P123/JS-K showed more in vivo anti-tumor activity than free JS-K. PMID:25330743

Effect of a Pluronic(®) P123 formulation on the nitric oxide-generating drug JS-K.

PubMed

Kaur, Imit; Kosak, Ken M; Terrazas, Moises; Herron, James N; Kern, Steven E; Boucher, Kenneth M; Shami, Paul J

2015-04-01

O(2)-(2,4-dinitrophenyl)1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate] or JS-K is a nitric oxide-producing prodrug of the arylated diazeniumdiolate class with promising anti-tumor activity. JS-K has challenging solubility and stability properties. We aimed to characterize and compare Pluronic(®) P123-formulated JS-K (P123/JS-K) with free JS-K. We determined micelle size, shape, and critical micelle concentration of Pluronic(®) P123. Efficacy was evaluated in vitro using HL-60 and U937 cells and in vivo in a xenograft in NOD/SCID IL2Rγ (null) mice using HL-60 cells. We compared JS-K and P123/JS-K stability in different media. We also compared plasma protein binding of JS-K and P123/JS-K. We determined the binding and Stern Volmer constants, and thermodynamic parameters. Spherical P123/JS-K micelles were smaller than blank P123. P123/JS-K formulation was more stable in buffered saline, whole blood, plasma and RPMI media as compared to free JS-K. P123 affected the protein binding properties of JS-K. In vitro it was as efficacious as JS-K alone when tested in HL-60 and U937 cells and in vivo greater tumor regression was observed for P123/JS-K treated NOD/SCID IL2Rγ (null) mice when compared to free JS-K-treated NOD/SCID IL2Rγ (null) mice. Pluronic(®) P123 solubilizes, stabilizes and affects the protein binding characteristics of JS-K. P123/JS-K showed more in vivo anti-tumor activity than free JS-K.

Uranium contaminated drinking water linked to leukaemia-Revisiting a case study from South Africa taking alternative exposure pathways into account.

PubMed

Winde, Frank; Erasmus, Ewald; Geipel, Gerhard

2017-01-01

The paper presents results of a follow-up to an earlier study which established a geospatial link between naturally elevated uranium (U) levels in borehole water and haematological abnormalities in local residents serving as a proxy for leukaemia prevalent in the area. While the original study focussed on drinking water only, this paper also explores alternative exposure pathways including the inhalation of dust and the food chain. U-levels in grass and tissue of sheep generally reflect U-levels in nearby borehole water and exceed background concentrations by 20 to nearly 500 times. U-levels in sheep tissue increase with age of the animal. Wool showed the highest U-concentration followed by other non-consumable tissue such as hooves, teeth and bones. Lower levels occur in edible parts such as meat and inner organs. The U-deposition rate in wool is several orders of magnitudes higher than in bone as a known target organ. Wool is an easy-to-sample non-invasive bioindicator for U-levels in meat. Depending on the original water content, dried samples show up to 5 times higher U-levels than identical fresh material. Contaminated drinking water is the main exposure pathway for farm residents resulting in U-uptake rates exceeding the WHO's tolerable daily intake (TDI) limit by up to 900%. This is somewhat mitigated by the fact that U-speciation is dominated by a neutral calcium-uranyl-carbonate complex of relatively low toxicity. Commercially available household filters are able to significantly reduce U-levels in well water and are thus recommended as a short-term intervention. Based on average consumption rates sheep meat, as local staple food, accounts for 34% of the TDI for U. Indoor levels of radon should be monitored, too, since it is linked to both, U and leukaemia. With elevated U-levels being present in other geological formations across South Africa boreholes in these areas should be surveyed. Copyright © 2016 Elsevier B.V. All rights reserved.

[A brief history of treatments for childhood acute lymphoblastic leukaemia].

PubMed

Leverger, Guy; Baruchel, André; Schaison, Gérard

2009-10-01

Acute lymphoblastic leukaemia is the most frequent childhood malignancy. The first effective drugs, which provided only short-lived complete remission, started to be used in the 1950s. All the effective drugs currently in use were discovered in the 1960s, when the first multidrug chemotherapy regimens were shown to confer prolonged complete remission, raising the possibility of a cure. Simultaneously, progress in our knowledge of leukaemic cells, and the identification of prognostic factors such as leukocytosis, age, cytogenetic and molecular abnormalities, and the early therapeutic response of leukaemic cells, led to randomized multicenter national and international trials. As a result, the chance of cure increased gradually over the last three decades. In rich countries, the overall survival rate among children with acute lymphoblastic leukaemia now reaches 85 to 90%.

Three-dimensional organotypic co-culture model of intestinal epithelial cells and macrophages to study Salmonella enterica colonization patterns.

PubMed

Barrila, Jennifer; Yang, Jiseon; Crabbé, Aurélie; Sarker, Shameema F; Liu, Yulong; Ott, C Mark; Nelman-Gonzalez, Mayra A; Clemett, Simon J; Nydam, Seth D; Forsyth, Rebecca J; Davis, Richard R; Crucian, Brian E; Quiriarte, Heather; Roland, Kenneth L; Brenneman, Karen; Sams, Clarence; Loscher, Christine; Nickerson, Cheryl A

2017-01-01

Three-dimensional models of human intestinal epithelium mimic the differentiated form and function of parental tissues often not exhibited by two-dimensional monolayers and respond to Salmonella in key ways that reflect in vivo infections. To further enhance the physiological relevance of three-dimensional models to more closely approximate in vivo intestinal microenvironments encountered by Salmonella , we developed and validated a novel three-dimensional co-culture infection model of colonic epithelial cells and macrophages using the NASA Rotating Wall Vessel bioreactor. First, U937 cells were activated upon collagen-coated scaffolds. HT-29 epithelial cells were then added and the three-dimensional model was cultured in the bioreactor until optimal differentiation was reached, as assessed by immunohistochemical profiling and bead uptake assays. The new co-culture model exhibited in vivo-like structural and phenotypic characteristics, including three-dimensional architecture, apical-basolateral polarity, well-formed tight/adherens junctions, mucin, multiple epithelial cell types, and functional macrophages. Phagocytic activity of macrophages was confirmed by uptake of inert, bacteria-sized beads. Contribution of macrophages to infection was assessed by colonization studies of Salmonella pathovars with different host adaptations and disease phenotypes (Typhimurium ST19 strain SL1344 and ST313 strain D23580; Typhi Ty2). In addition, Salmonella were cultured aerobically or microaerobically, recapitulating environments encountered prior to and during intestinal infection, respectively. All Salmonella strains exhibited decreased colonization in co-culture (HT-29-U937) relative to epithelial (HT-29) models, indicating antimicrobial function of macrophages. Interestingly, D23580 exhibited enhanced replication/survival in both models following invasion. Pathovar-specific differences in colonization and intracellular co-localization patterns were observed. These findings emphasize the power of incorporating a series of related three-dimensional models within a study to identify microenvironmental factors important for regulating infection.

CD33 monoclonal antibody conjugated Au cluster nano-bioprobe for targeted flow-cytometric detection of acute myeloid leukaemia

NASA Astrophysics Data System (ADS)

Retnakumari, Archana; Jayasimhan, Jasusri; Chandran, Parwathy; Menon, Deepthy; Nair, Shantikumar; Mony, Ullas; Koyakutty, Manzoor

2011-07-01

Protein stabilized gold nanoclusters (Au-NCs) are biocompatible, near-infrared (NIR) emitting nanosystems having a wide range of biomedical applications. Here, we report the development of a Au-NC based targeted fluorescent nano-bioprobe for the flow-cytometric detection of acute myeloid leukaemia (AML) cells. Au-NCs with ~ 25-28 atoms showing bright red-NIR fluorescence (600-750 nm) and average size of ~ 0.8 nm were prepared by bovine serum albumin assisted reduction-cum-stabilization in aqueous phase. The protein protected clusters were conjugated with monoclonal antibody against CD33 myeloid antigen, which is overexpressed in ~ 99.2% of the primitive population of AML cells, as confirmed by immunophenotyping using flow cytometry. Au-NC-CD33 conjugates having average size of ~ 12 nm retained bright fluorescence over an extended duration of ~ a year, as the albumin protein protects Au-NCs against degradation. Nanotoxicity studies revealed excellent biocompatibility of Au-NC conjugates, as they showed no adverse effect on the cell viability and inflammatory response. Target specificity of the conjugates for detecting CD33 expressing AML cells (KG1a) in flow cytometry showed specific staining of ~ 95.4% of leukaemia cells within 1-2 h compared to a non-specific uptake of ~ 8.2% in human peripheral blood cells (PBMCs) which are CD33low. The confocal imaging also demonstrated the targeted uptake of CD33 conjugated Au-NCs by leukaemia cells, thus confirming the flow cytometry results. This study demonstrates that novel nano-bioprobes can be developed using protein protected fluorescent nanoclusters of Au for the molecular receptor targeted flow cytometry based detection and imaging of cancer cells.

Delayed translational silencing of ceruloplasmin transcript in gamma interferon-activated U937 monocytic cells: role of the 3' untranslated region

NASA Technical Reports Server (NTRS)

Mazumder, B.; Fox, P. L.

1999-01-01

Ceruloplasmin (Cp) is an acute-phase protein with ferroxidase, amine oxidase, and pro- and antioxidant activities. The primary site of Cp synthesis in human adults is the liver, but it is also synthesized by cells of monocytic origin. We have shown that gamma interferon (IFN-gamma) induces the synthesis of Cp mRNA and protein in monocytic cells. We now report that the induced synthesis of Cp is terminated by a mechanism involving transcript-specific translational repression. Cp protein synthesis in U937 cells ceased after 16 h even in the presence of abundant Cp mRNA. RNA isolated from cells treated with IFN-gamma for 24 h exhibited a high in vitro translation rate, suggesting that the transcript was not defective. Ribosomal association of Cp mRNA was examined by sucrose centrifugation. When Cp synthesis was high, i.e., after 8 h of IFN-gamma treatment, Cp mRNA was primarily associated with polyribosomes. However, after 24 h, when Cp synthesis was low, Cp mRNA was primarily in the nonpolyribosomal fraction. Cytosolic extracts from cells treated with IFN-gamma for 24 h, but not for 8 h, contained a factor which blocked in vitro Cp translation. Inhibitor expression was cell type specific and present in extracts of human cells of myeloid origin, but not in several nonmyeloid cells. The inhibitory factor bound to the 3' untranslated region (3'-UTR) of Cp mRNA, as shown by restoration of in vitro translation by synthetic 3'-UTR added as a "decoy" and detection of a binding complex by RNA gel shift analysis. Deletion mapping of the Cp 3'-UTR indicated an internal 100-nucleotide region of the Cp 3'-UTR that was required for complex formation as well as for silencing of translation. Although transcript-specific translational control is common during development and differentiation and global translational control occurs during responses to cytokines and stress, to our knowledge, this is the first report of translational silencing of a specific transcript following cytokine activation.

Antibody therapy for acute myeloid leukaemia.

PubMed

Gasiorowski, Robin E; Clark, Georgina J; Bradstock, Kenneth; Hart, Derek N J

2014-02-01

Novel therapies with increased efficacy and decreased toxicity are desperately needed for the treatment of acute myeloid leukaemia (AML). The anti CD33 immunoconjugate, gemtuzumab ozogamicin (GO), was withdrawn with concerns over induction mortality and lack of efficacy. However a number of recent trials suggest that, particularly in AML with favourable cytogenetics, GO may improve overall survival. This data and the development of alternative novel monoclonal antibodies (mAb) have renewed interest in the area. Leukaemic stem cells (LSC) are identified as the subset of AML blasts that reproduces the leukaemic phenotype upon transplantation into immunosuppressed mice. AML relapse may be caused by chemoresistant LSC and this has refocused interest on identifying and targeting antigens specific for LSC. Several mAb have been developed that target LSC effectively in xenogeneic models but only a few have begun clinical evaluation. Antibody engineering may improve the activity of potential new therapeutics for AML. The encouraging results seen with bispecific T cell-engaging mAb-based molecules against CD19 in the treatment of B-cell acute lymphobalstic leukaemia, highlight the potential efficacy of engineered antibodies in the treatment of acute leukaemia. Potent engineered mAb, possibly targeting novel LSC antigens, offer hope for improving the current poor prognosis for AML. © 2013 John Wiley & Sons Ltd.

A new inhibitor of synovial phospholipase A2 from fermentations of Penicillium sp. 62-92.

PubMed

Witter, L; Anke, T; Sterner, O

1998-01-01

Penidiamide, a new tripetide containing dehydrotryptamine, glycine and anthranilic acid linked together by two amide bonds, and oxindole were isolated from submerged cultures of Penicillium sp. 62-92. Both compounds preferentially inhibited human synovial phospholipase A2, penidiamide with an IC50 of 30 microM and oxindole of 380 microM. With the exception of U 937 cells (leukemia, human), no cytotoxic activities were detected against HL-60- (leukemia, human), HeLa S3- (epitheloid carcinoma, human), BHK 21- (kidney fibroblasts, hamster), and L1210-cells (leukemia, mouse). No antimicrobial activity was detected for oxindole, and only weak antibacterial activity for penidiamide. The structure of penidiamide was elucidated by spectroscopic methods.

Primary lymphocytic lymphoma of lacrimal gland.

PubMed

Romero-Caballero, M D; Lozano-García, I; Gómez-Molina, C; Gil-Liñán, A I; Arcas, I

2017-02-01

We report a case of primary small-cell lymphocytic lacrimal gland lymphoma in a male diagnosed with primary antiphospholipid syndrome. These rare lymphomas are usually presented in the clinic as disseminations secondary to chronic lymphocytic leukaemia, and the primary site is rare in the orbit. Non-Hodgkin lymphomas are a heterogeneous group of tumours. Although treatment in the IE stage is usually radiotherapy, due to its association with antiphospholipid syndrome, systemic treatment with rituximab was administered. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Cryptococcal meningoencephalitis in patients with mantle cell lymphoma on ibrutinib.

PubMed

Sun, Kai; Kasparian, Saro; Iyer, Swaminathan; Pingali, Sai Ravi

2018-01-01

Ibrutinib, a Bruton's tyrosine kinase inhibitor, has been increasingly widely used in relapsed and refractory mantle cell lymphoma (MCL) and chronic lymphocytic leukaemia [1, 2]. With its use becoming more common, there have been emerging case reports of opportunistic infections like cryptococcal infections [3-8]. These infections in patients receiving ibrutinib were mostly reported in patients with chronic lymphocytic leukaemia, who have poor immune reconstitution. Here, we report two cases of cryptococcal meningoencephalitis in patients with MCL on ibrutinib.

Holoprosencephaly and Pure Red Cell Aplasia in a Feline Leukaemia Virus-Positive Kitten.

PubMed

Southard, T L; Rodriguez-Ramos Fernandez, J; Priest, H; Stokol, T

2016-01-01

A 9-month-old, female, domestic longhair cat with severe anaemia tested positive for feline leukaemia virus (FeLV) and was humanely destroyed and submitted for necropsy examination. Gross findings included a non-divided rostral telencephalon, consistent with semilobar holoprosencephaly. Histological examination of the bone marrow revealed an almost complete absence of erythroid precursor cells, consistent with pure red cell aplasia, and mild to moderate myelofibrosis. This case demonstrates a very unusual central nervous system defect, as well as an atypical presentation of pure red cell aplasia, in a FeLV-positive kitten. Copyright © 2016 Elsevier Ltd. All rights reserved.

Acute erythremic myelosis (true erythroleukaemia): a variant of AML FAB-M6.

PubMed

Hasserjian, R P; Howard, J; Wood, A; Henry, K; Bain, B

2001-03-01

Classic erythroleukaemia (acute myeloid leukaemia M6, or M6 AML) is defined as an excess of myeloblasts in an erythroid predominant background. Leukaemia variants in which the primitive blast cells are demonstrably erythroid are extremely rare and poorly characterised. Variably referred to as "true erythroleukaemia" or "acute erythremic myelosis", they are often included within the M6 AML category even though they do not meet strict criteria for this type of AML. Two cases of acute erythroid neoplasia are presented with clinical, morphological, immunophenotypic, and cytogenetic analysis. Both patients presented with profound anaemia, one in a setting of long standing myelodysplasia. Bone marrow examination revealed a predominant population of highly dysplastic erythroid cells in both cases. In one case, the liver was infiltrated by neoplastic erythroid cells. Both patients died within four months of diagnosis. This report illustrates that cases of acute leukaemia occur in which the dominant neoplastic cell is a primitive erythroid cell without an accompanying increase in myeloblasts. This does not preclude the neoplastic clone originating in a multipotent haemopoietic stem cell, as suggested by cases arising in patients with myelodysplasia. Acute erythremic myelosis should be recognised as a distinct variant of M6 AML.

Molecular effects of the phosphatidylinositol-3-kinase inhibitor NVP-BKM120 on T and B-cell acute lymphoblastic leukaemia.

PubMed

Pereira, João Kleber Novais; Machado-Neto, João Agostinho; Lopes, Matheus Rodrigues; Morini, Beatriz Corey; Traina, Fabiola; Costa, Fernando Ferreira; Saad, Sara Teresinha Olalla; Favaro, Patricia

2015-09-01

Constitutive activation of the PI3K pathway in T cell acute lymphoblastic leukaemia (T-ALL) has been reported and in a mouse model, PI3K activation, together with MYC, cooperates in Burkitt lymphoma (BL) pathogenesis. We investigated the effects of NVP-BKM120, a potent pan-class I PI3K inhibitor, in lymphoblastic leukaemia cell lines. Effects of NVP-BKM120 on cell viability, clonogenicity, apoptosis, cell cycle, cell signalling and autophagy were assessed in vitro on T-ALL (Jurkat and MOLT-4) and BL (Daudi and NAMALWA) cell lines. NVP-BKM120 treatment decreased cell viability and clonogenic growth in all tested cells. Moreover, the drug arrested cell cycling in association with a decrease in Cyclin B1 protein levels, and increased apoptosis. Immunoblotting analysis of cells treated with the drug revealed decreased phosphorylation, in a dose-dependent manner, of AKT, mTOR, P70S6K and 4EBP1, with stable total protein levels. Additionally, we observed a dose-dependent decrease in BAD phosphorylation, in association with augmented BAX:BCL2 ratio. Quantification of autophagy showed a dose-dependent increase in acidic vesicular organelles in all cells tested. In summary, our present study establishes that NVP-BKM120 presents an effective antitumour activity against T-ALL and BL cell lines. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adult T-cell leukaemia/lymphoma can mimic other lymphomas in a non-endemic area: dilemmas in diagnosis and treatment.

PubMed

Huang, C-T; Lee, Y-H; Chow, K-C; Yang, C-F; Chen, P C-H; Hsiao, L-T; Gau, J-P; Tzeng, C-H; Liu, C-Y; Chiou, T-J

2014-04-01

The diagnosis of Adult T-cell leukaemia/lymphoma (ATL) in non-endemic regions is challenging. This study analyses the clinicopathologic features and diagnostic processes of ATL patients in Taiwan. ATL patients diagnosed and treated at Taipei Veterans General Hospital from 1998 through 2010 were retrospectively identified. The diagnosis of ATL was confirmed by in situ detection of human T-cell leukaemia virus type 1 (HTLV-1) when necessary. Patients' data were reviewed and analysed. Fourteen ATL patients were identified, among whom six (42.9%) had an antecedent diagnosis of other malignant lymphomas before the ATL diagnosis, including two diagnosed with Hodgkin disease (HD), one with peripheral T-cell lymphoma, two with chronic lymphocytic leukaemia and one with angioimmunoblastic T-cell lymphoma. Of the 14 patients, eight (57%) were subclassified as the acute type, three (21.4%) as the lymphoma type, and three (21.4%) as the chronic type ATL. Five of six (83.3%) patients with initial non-ATL misdiagnosis were diagnosed with non-acute type ATL. In particular, a patient with an antecedent diagnosis of HD presented with typical Reed-Sternberg (RS)-like cells harbouring Epstein-Barr virus genomes in affected lymph nodes. The patient progressed to acute type ATL 3 years after the initial diagnosis, and HTLV-1 genomes were identified in the previous RS-like cells. In non-endemic areas, such as Taiwan, ATL, particularly the non-acute type, may mimic other lymphomas and easily be misdiagnosed. HTLV-1 serology should be routinely screened in all malignant lymphoma patients. In situ detection of HTLV-1 is helpful in cases with diagnostic dilemmas. © 2014 The Authors; Internal Medicine Journal © 2014 Royal Australasian College of Physicians.

mTOR signaling promotes foam cell formation and inhibits foam cell egress through suppressing the SIRT1 signaling pathway.

PubMed

Zheng, Haixiang; Fu, Yucai; Huang, Yusheng; Zheng, Xinde; Yu, Wei; Wang, Wei

2017-09-01

Atherosclerosis (AS) is a chronic immuno‑inflammatory disease accompanied by dyslipidemia. The authors previously demonstrated that sirtuin 1 (SIRT1) may prevent atherogenesis through influencing the liver X receptor/C‑C chemokine receptor type 7/nuclear factor‑κB (LXR‑CCR7/NF‑κB) signaling pathway. Previous studies have suggested a role for mammalian target of rapamycin (mTOR) signaling in the pathogenesis of cardiovascular diseases. The present study investigated the potential association between mTOR signaling and SIRT1‑LXR‑CCR7/NF‑κB signaling (SIRT1 signaling) in AS pathogenesis. To induce foam cell formation, U937 cells were differentiated into macrophages by exposure to phorbol 12‑myristate 13‑acetate (PMA) for 24 h, followed by treatment with palmitate and oxidized low density lipoprotein for a further 24 h. Oil red O staining revealed a large accumulation of lipid droplets present in foam cells. Western blot analysis demonstrated increased protein levels of phosphorylated (p)‑mTOR and its downstream factor p‑ribosomal protein S6 kinase (p70S6K). Reverse transcription‑quantitative polymerase chain reaction and western blot analyses additionally revealed decreased expression of SIRT1, LXRα and CCR7 and increased expression of NF‑κB and its downstream factor tumor necrosis factor‑α (TNF‑α) in an atherogenetic condition induced by lysophosphatidic acid (LPA). In addition, abundant lipid droplets accumulated in U937‑LPA‑treated foam cells. Rapamycin, an mTOR inhibitor, suppressed the expression and activity of mTOR and p70S6K, however enhanced expression of SIRT1, LXRα, and CCR7. Conversely, rapamycin deceased TNF‑α and NF‑κB activity, the latter of which was further confirmed by immunofluorescence analysis demonstrating increased levels of NF‑κB present in the cytoplasm compared with the nucleus. The findings of the present study suggest that mTOR signaling promotes foam cell formation and inhibits foam cell egress via suppression of SIRT1 signaling.

Progressive trichodysplasia spinulosa in a patient with chronic lymphocytic leukaemia in remission.

PubMed

Lee, Joyce S-S; Frederiksen, Peter; Kossard, Steven

2008-02-01

A 70-year old Caucasian man with chronic lymphocytic leukaemia developed trichodysplasia spinulosa 2 months after ceasing chemotherapy. Histological features characteristic to this condition include dilated and enlarged hair follicles, hyperplastic hair bulbs, hyperplasia of inner root sheath cells with numerous large, eosinophilic, trichohyaline granules, and hypercornification. Although he was in remission for chronic lymphocytic leukaemia, lesions were slowly progressive 15 months after cessation of chemotherapy. We also describe a painless pull-test where spicules can be easily plucked and assessed microscopically for inner root sheath keratinization, or observed with surface microscopy in a clinic setting.

Radio Frequency Emitter Geolocation Using Cubesats

DTIC Science & Technology

2014-03-27

CUBESATS Andrew J. Small, B.S.E.E. Captain, USAF Approved: //signed// Maj Marshall Haker , PhD (Chairman) //signed// Jonathan Black, PhD (Member) //signed...Cubesat, Direct Position Determination, Angle of Arrival, Time Difference of Arrival, Instantaneous Received Frequency U U U UU 101 Maj Marshall Haker (ENG) (937) 255-3636 x4603 marshall.haker@afit.edu

Active acute leukaemia: should transplant be offered to all patients?

PubMed

Avni, Batia; Shapira, Michael Y; Resnick, Igor B; Stepensky, Polina; Or, Reuven; Grisariu, Sigal

2017-12-01

The probability of achieving long term remission for patients with refractory acute leukaemia is very low. Allogeneic stem cell transplantation (SCT) is offered to these patients in order to improve their dismal outcome. We retrospectively analyzed 361 acute leukaemia patients, who underwent allogeneic SCT in the Hadassah's bone marrow transplantation department between the years 2005 and 2012 and identified 84 patients with active leukaemia at transplantation. Median age was 34 years. Sixty four patients were diagnosed with acute myeloid leukaemia (AML), 18 patients with acute lymphoblastic leukaemia and two with biphenotypic leukaemia. The majority of patients were diagnosed with de-novo AML and transplanted at relapse. In the surviving patients, median follow up was 15 months. One year OS was 20%. At time of last follow up, 13 patients were alive (15.5%): ten patients with AML and two patients with acute lymphoblastic leukaemia. In the univariate analysis, factors associated with significantly better overall survival were as follows: matched unrelated donor (p = 0.006), matched donor (p = 0.014) and occurrence of acute graft-versus-host disease (aGVHD) (p = 0.019). Karnofsky performance score at SCT and occurrence of cGVHD were found to be borderline significant. Only matched unrelated donor and aGVHD were found to affect overall survival significantly in the multivariate analysis. Other than performance score at SCT, none of the pretransplant patients' characteristics were found to influence survival. In conclusion, as none of the pretransplant characteristics were found to influence the ability to select the patients that will benefit from HSC transplantation, this work supports offering HSCT to all active leukaemia eligible patients with reasonable performance status. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Pattern Of Leukaemia Patients Admitted In Ayub Teaching Hospital Abbottabad.

PubMed

Khan, Tariq Mehmood

2016-01-01

Any tissue of the body can give rise to cancer. However, those tissues which multiply rapidly are at high risk of developing cancer and haematopoietic system is one of them. Neoplasms of this system are known as leukaemia and lymphoma, according to the types of white cells involved. Study of cancer patterns in different societies, however can contribute a substantial knowledge about the aetiology of cancer. The present Study was designed and aimed to estimate the frequency of different types of leukaemia in patients admitted in Ayub Teaching hospital Abbottabad. Data from the patients admitted at oncology Department of Ayub Teaching Hospital Abbottabad from 2010 to 2015 was collected and analysed to calculate cumulative and year-wise frequency of leukaemia and its major types. Frequency distribution with reference to gender and age was also calculated. In our analysis about 16% patients had acute myelocytic leukaemia and 32% patients had acute lymphocytic leukaemia; while chronic myeloid leukaemia outnumbered chronic lymphocytic leukaemia (11% and 3%); Hodgkin lymphoma was seen in 18% cases while Non Hodgkin lymphoma (NHL) was present in 20% cases. Out of the total, 150 cases (75%) belonged to mountainous areas of Hazara, i.e., 40 cases belonged to Kohistan, another 40 cases were residents of Battagram, 45 cases belonged to hilly areas of Mansehra and 25 cases to Kaghan valley, while only 50 (25%) cases were from the plain areas of Abbottabad and Haripur districts, i.e., 20 and 30 cases respectively. Leukaemia is more common in hilly areas of Hazara, since majority of the cases belonged to well-known mountainous regions of Kohistan, Battagram, Kaghan or Mansehra and only few cases belonged to the plain areas of Abbottabad and Haripur districts.

A novel serine protease predominately expressed in macrophages.

PubMed Central

Chen, Cailin; Darrow, Andrew L; Qi, Jian-Shen; D'Andrea, Michael R; Andrade-Gordon, Patricia

2003-01-01

We have identified a novel serine protease designated EOS by sequence identity searches. The deduced protein contains 284 amino acids with an active form containing 248 amino acids starting from an Ile-Val-Gly-Gly motif. The active form comprises a catalytic triad of conserved amino acids: His77, Asp126 and Ser231. It shares 44% identity with beta-tryptase and belongs to the S1 trypsin-like serine-protease family. Interestingly, this gene also maps to human chromosome 16p13.3. The purified protease showed amidolytic activity, cleaving its substrates before arginine residues. Tissue distribution by immunohistochemistry analysis demonstrated that EOS is highly expressed in spleen and moderately expressed in intestine, colon, lung and brain. We confirmed this expression pattern at the mRNA level by performing in situ hybridization. The results from both immunohistochemistry and in situ hybridization indicate that EOS is associated with macrophages. We corroborated this observation by double immunofluorescence using the anti-EOS antibody and an anti-CD68 antibody, a macrophage specific marker. Furthermore, we have detected a dramatic increase in immune staining of EOS in cultured U937 cells treated with PMA, which represent activated macrophages. This up-regulation is also reflected by elevated EOS mRNA in the PMA-treated U937 cells detected by Northern blotting. Since macrophages have important roles in various pathological conditions, such as wound healing, atherosclerosis and numerous inflammatory diseases, the localization of this novel serine protease to active macrophages may help to further the elucidation of the roles of this gene product in modulating these disorders. PMID:12795636

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szymanska, Ewelina; Korzeniowski, Marek; Raynal, Patrick

Receptor Fc{gamma}IIA (Fc{gamma}RIIA) associates with plasma membrane rafts upon activation to trigger signaling cascades leading to actin polymerization. We examined whether compartmentalization of PI(4,5)P{sub 2} and PI(4,5)P{sub 2}-synthesizing PIP5-kinase I{alpha} to rafts contributes to Fc{gamma}RIIA signaling. A fraction of PIP5-kinase I{alpha} was detected in raft-originating detergent-resistant membranes (DRM) isolated from U937 monocytes and other cells. The DRM of U937 monocytes contained also a major fraction of PI(4,5)P{sub 2}. PIP5-kinase I{alpha} bound PI(4,5)P{sub 2}, and depletion of the lipid displaced PIP5-kinase I{alpha} from the DRM. Activation of Fc{gamma}RIIA in BHK transfectants led to recruitment of the kinase to the plasma membranemore » and enrichment of DRM in PI(4,5)P{sub 2}. Immunofluorescence studies revealed that in resting cells the kinase was associated with the plasma membrane, cytoplasmic vesicles and the nucleus. After Fc{gamma}RIIA activation, PIP5-kinase I{alpha} and PI(4,5)P{sub 2} co-localized transiently with the activated receptor at distinct cellular locations. Immunoelectron microscopy studies revealed that PIP5-kinase I{alpha} and PI(4,5)P{sub 2} were present at the edges of electron-dense assemblies containing activated Fc{gamma}RIIA in their core. The data suggest that activation of Fc{gamma}RIIA leads to membrane rafts coalescing into signaling platforms containing PIP5-kinase I{alpha} and PI(4,5)P{sub 2}.« less

Apoptosis inhibitor of macrophage (AIM) expression in alveolar macrophages in COPD

PubMed Central

2013-01-01

Background Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the setting of cigarette smoke extract (CSE) exposure. Methods Immunohistochemical evaluations of AIM were performed. Immunostaining was assessed by counting total and positively staining AM numbers in each case (n = 5 in control, n = 5 in non-COPD smoker, n = 5 in COPD). AM were isolated from bronchoalveolar lavage fluid (BALF). The changes of AIM expression levels in response to CSE exposure in AM were evaluated. Knock-down of anti-apoptotic Bcl-xL was mediated by siRNA transfection. U937 monocyte-macrophage cell line was used to explore the anti-apoptotic properties of AIM. Results The numbers of AM and AIM-positive AM were significantly increased in COPD lungs. AIM expression was demonstrated at both mRNA and protein levels in isolated AM, which was enhanced in response to CSE exposure. AIM significantly increased Bcl-xL expression levels in AM and Bcl-xL was involved in a part of anti-apoptotic mechanisms of AIM in U937 cells in the setting of CSE exposure. Conclusions These results suggest that AIM expression in association with cigarette smoking may be involved in accumulation of AM in COPD. PMID:23497247

Magnoflorine Enhances LPS-Activated Pro-Inflammatory Responses via MyD88-Dependent Pathways in U937 Macrophages.

PubMed

Haque, Md Areeful; Jantan, Ibrahim; Harikrishnan, Hemavathy; Abdul Wahab, Siti Mariam

2018-06-15

Magnoflorine, a major bioactive metabolite isolated from Tinospora crispa, has been reported for its diverse biochemical and pharmacological properties. However, there is little report on its underlying mechanisms of action on immune responses, particularly on macrophage activation. In this study, we aimed to investigate the effects of magnoflorine, isolated from T. crispa on the pro-inflammatory mediators generation induced by LPS and the concomitant NF- κ B, MAPKs, and PI3K-Akt signaling pathways in U937 macrophages. Differentiated U937 macrophages were treated with magnoflorine and the release of pro-inflammatory mediators was evaluated through ELISA, while the relative mRNA expression of the respective mediators was quantified through qRT-PCR. Correspondingly, western blotting was executed to observe the modulatory effects of magnoflorine on the expression of various markers related to NF- κ B, MAPK and PI3K-Akt signaling activation in LPS-primed U937 macrophages. Magnoflorine significantly enhanced the upregulation of TNF- α , IL-1 β , and PGE 2 production as well as COX-2 protein expression. Successively, magnoflorine prompted the mRNA transcription level of these pro-inflammatory mediators. Magnoflorine enhanced the NF- κ B activation by prompting p65, I κ B α , and IKK α / β phosphorylation as well as I κ B α degradation. Besides, magnoflorine treatments concentration-dependently augmented the phosphorylation of JNK, ERK, and p38 MAPKs as well as Akt. The immunoaugmenting effects were further confirmed by investigating the effects of magnoflorine on specific inhibitors, where the treatment with specific inhibitors of NF- κ B, MAPKs, and PI3K-Akt proficiently blocked the magnoflorine-triggered TNF- α release and COX-2 expression. Magnoflorine furthermore enhanced the MyD88 and TLR4 upregulation. The results suggest that magnoflorine has high potential on augmenting immune responses. Georg Thieme Verlag KG Stuttgart · New York.

Erosion of the chronic myeloid leukaemia stem cell pool by PPARγ agonists.

PubMed

Prost, Stéphane; Relouzat, Francis; Spentchian, Marc; Ouzegdouh, Yasmine; Saliba, Joseph; Massonnet, Gérald; Beressi, Jean-Paul; Verhoeyen, Els; Raggueneau, Victoria; Maneglier, Benjamin; Castaigne, Sylvie; Chomienne, Christine; Chrétien, Stany; Rousselot, Philippe; Leboulch, Philippe

2015-09-17

Whether cancer is maintained by a small number of stem cells or is composed of proliferating cells with approximate phenotypic equivalency is a central question in cancer biology. In the stem cell hypothesis, relapse after treatment may occur by failure to eradicate cancer stem cells. Chronic myeloid leukaemia (CML) is quintessential to this hypothesis. CML is a myeloproliferative disorder that results from dysregulated tyrosine kinase activity of the fusion oncoprotein BCR-ABL. During the chronic phase, this sole genetic abnormality (chromosomal translocation Ph(+): t(9;22)(q34;q11)) at the stem cell level causes increased proliferation of myeloid cells without loss of their capacity to differentiate. Without treatment, most patients progress to the blast phase when additional oncogenic mutations result in a fatal acute leukaemia made of proliferating immature cells. Imatinib mesylate and other tyrosine kinase inhibitors (TKIs) that target the kinase activity of BCR-ABL have improved patient survival markedly. However, fewer than 10% of patients reach the stage of complete molecular response (CMR), defined as the point when BCR-ABL transcripts become undetectable in blood cells. Failure to reach CMR results from the inability of TKIs to eradicate quiescent CML leukaemia stem cells (LSCs). Here we show that the residual CML LSC pool can be gradually purged by the glitazones, antidiabetic drugs that are agonists of peroxisome proliferator-activated receptor-γ (PPARγ). We found that activation of PPARγ by the glitazones decreases expression of STAT5 and its downstream targets HIF2α and CITED2, which are key guardians of the quiescence and stemness of CML LSCs. When pioglitazone was given temporarily to three CML patients in chronic residual disease in spite of continuous treatment with imatinib, all of them achieved sustained CMR, up to 4.7 years after withdrawal of pioglitazone. This suggests that clinically relevant cancer eradication may become a generally attainable goal by combination therapy that erodes the cancer stem cell pool.

Silver nanoparticles exhibit size-dependent differential toxicity and induce expression of syncytin-1 in FA-AML1 and MOLT-4 leukaemia cell lines.

PubMed

Alqahtani, Sultan; Promtong, Pawika; Oliver, Anthony W; He, Xiaotong T; Walker, Thomas D; Povey, Andrew; Hampson, Lynne; Hampson, Ian N

2016-11-01

Human endogenous retrovirus (HERV) sequences make up ~8% of the human genome and increased expression of some HERV proteins has been observed in various pathologies including leukaemia and multiple sclerosis. However, little is known about the function of these HERV proteins or environmental factors which regulate their expression. Silver nanoparticles (AgNPs) are used very extensively as antimicrobials and antivirals in numerous consumer products although their effect on the expression of HERV gene products is unknown. Cell proliferation and cell toxicity assays were carried out on human acute T lymphoblastic leukaemia (MOLT-4) and Fanconi anaemia associated acute myeloid leukaemia (FA-AML1) cells treated with two different sizes of AgNPs (7nm and 50nm diameter). Reverse-transcriptase polymerase chain reaction and western blotting were then used to the assess expression of HERV-W syncytin-1 mRNA and protein in these cells. FA-AML1 cells were more sensitive overall than MOLT-4 to treatment with the smaller 7nm sized AgNp's being the most toxic in these cells. MOLT-4 cell were more resistant and showed no evidence of differential toxicity to the different sized particles. Syncytin-1 mRNA and protein were induced by both 7 and 50nm AgNPs in both cell types yet with different kinetics. In summary, the observation that AgNPs induce expression of syncytin-1 in FA-AML1 and MOLT-4 cells at doses as little as 5 µg/ml is grounds for concern since this protein is up-regulated in both malignant and neurodegenerative diseases. Considering the widespread use of AgNPs in the environment it is clear that their ability to induce syncytin-1 should be investigated further in other cell types. © The Author 2016. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Crystalline inclusions in the cytoplasm and nuclei of cells of acute myeloid leukaemia.

PubMed

Pearson, E C

1989-01-01

In a survey by electron microscopy of peripheral blood and/or bone marrow from 230 adult patients with acute myeloid leukaemia, five were observed to contain crystalline inclusions in the cytoplasm of the leukaemic cells and a sixth contained crystals in the nuclei. In four cases, two of FAB type M2 and two of M4, the cytoplasmic crystals were hexagonal in section and 1-2 micron long. Two examples showed internal periodicities in the range 3.3-4.0 nm when the electronmicrographs were analysed by optical diffractometry. A single case of M1 contained smaller trapezoidal crystals with a 4.9nm periodicity. The sixth patient, with unusual cytological abnormalities and a rare t(3; 6) chromosomal translocation, contained six-sided crystals in the nuclei of some relatively undifferentiated cells. To the best of our knowledge such intranuclear crystals have not previously been reported in leukaemia. The relevance of the crystals to the leukaemic process is discussed.

Angiogenic factors in chronic lymphocytic leukaemia (CLL): Where do we stand?

PubMed

Aguirre Palma, Luis Mario; Gehrke, Iris; Kreuzer, Karl-Anton

2015-03-01

The role of angiogenesis in haematological malignancies such as chronic lymphocytic leukaemia (CLL) is difficult to envision, because leukaemia cells are not dependent on a network of blood vessels to support basic physiological requirements. Regardless, CLL cells secrete high levels of major angiogenic factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and platelet derived growth factor (PDGF). Nonetheless, it remains unclear how most angiogenic factors regulate accumulation and delayed apoptosis of CLL cells. Angiogenic factors such as leptin, granulocyte colony-stimulating factor (G-CSF), follistatin, angiopoietin-1 (Ang1), angiogenin (ANG), midkine (MK), pleiotrophin (PTN), progranulin (PGRN), proliferin (PLF), placental growth factor (PIGF), and endothelial locus-1 (Del-1), represent novel therapeutic targets of future CLL research but have remained widely overlooked. This review aims to outline our current understanding of angiogenic growth factors and their relationship with CLL, a still uncured haematopoietic malignancy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

[Relapse of acute promyelocytic leukemia in the central nervous system revealed by isolated dementia].

PubMed

Colin, O; Julian, A; Puyade, M; Bouyer, S; Meurin, E; Blondeau, S; Houeto, J L; Neau, J P

2016-12-01

Approximately 1.5% of dementia is due to curable aetiology. We report an isolated dementia syndrome due to a meningeal relapse of acute promyelocytic leukaemia with favourable outcome after appropriate treatment. A 72-year-old woman, in remission of an acute promyelocytic leukaemia, presented a loss of autonomy for several months due to corticosubcortical dementia. Lumbar puncture showed blast cells indicating meningeal relapse of leukaemia. Intrathecal chemotherapy and arsenic trioxide obtained biological and molecular remission as well as restoration of normal cognitive functions. In patients with hematologic past history such as acute promyelocytic leukaemia, an isolated cognitive impairment should alert physicians to search for an isolated neuromeningeal relapse. Copyright © 2016 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Infusion of a non-HLA-matched ex-vivo expanded cord blood progenitor cell product after intensive acute myeloid leukaemia chemotherapy: a phase 1 trial.

PubMed

Delaney, Colleen; Milano, Filippo; Cicconi, Laura; Othus, Megan; Becker, Pamela S; Sandhu, Vicky; Nicoud, Ian; Dahlberg, Ann; Bernstein, Irwin D; Appelbaum, Frederick R; Estey, Elihu H

2016-07-01

The intensive chemotherapy regimens used to treat acute myeloid leukaemia routinely result in serious infections, largely due to prolonged neutropenia. We investigated the use of non-HLA-matched ex-vivo expanded cord blood progenitor cells to accelerate haemopoietic recovery and reduce infections after chemotherapy. We enrolled patients with a diagnosis of acute myeloid leukaemia by WHO criteria and aged 18-70 years inclusive at our institution (Fred Hutchinson Cancer Research Center) into this phase 1 trial. The primary endpoint of the study was safety of infusion of non-HLA-matched expanded cord blood progenitor cells after administration of clofarabine, cytarabine, and granulocyte-colony stimulating factor priming. The protocol is closed to accrual and analysis was performed per protocol. The trial is registered with ClinicalTrials.gov, NCT01031368. Between June 29, 2010, and June 26, 2012, 29 patients with acute myeloid leukaemia (19 newly diagnosed, ten relapsed or refractory) were enrolled. The most common adverse events were fever (27 [93%] of 29 patients) and infections (25 [86%] of 29 patients). We observed one case of acute infusional toxicity (attributed to an allergic reaction to dimethyl sulfoxide) in the 29 patients enrolled, who received 42 infusions of expanded progenitor cells. The following additional serious but expected adverse events were observed (each in one patient): grade 4 atrial fibrillation, grade 4 febrile neutropenia, lung infection with grade 4 absolute neutrophil count, colon infection with grade 4 absolute neutrophil count, grade 4 changed mental status, and one death from liver failure. No unexpected toxicity or graft-versus-host disease was observed. There was no evidence of in-vivo persistence of the expanded progenitor cell product in any patient beyond 14 days or induced alloimmunisation. Infusion of the expanded progenitor cell product seemed safe and might provide a promising treatment method for patients with acute myeloid leukaemia. Biomedical Advanced Research and Development Authority in the US Department of Health and Human Services and Genzyme (Sanofi). Copyright © 2016 Elsevier Ltd. All rights reserved.

Single-cell immunofluorescence assay for terminal transferase: human leukaemic and non-leukaemic cells.

PubMed

Okamura, S; Crane, F; Jamal, N; Messner, H A; Mak, T W

1980-02-01

The characteristics of a single-cell immunofluorescence assay for terminal deoxynucleotidyl transferase (terminal transferase, TdT) is described. The data indicate that the single-cell immunofluorescence assay is highly efficient and specific for the detection of cells containing TdT. Using this assay, we have examined 124 marrow or peripheral-blood samples from 104 patients with or without haematological malignancies. Results indicate that TdT(+) cells from 6% to 100% were found in the following patients: 34/40 samples from patients with ALL at the time of diagnosis or during relapse; 2/3 patients with acute undifferentiated leukaemia; 2/3 patients with acute myelomonocytic leukaemia; 1/24 patients with acute myeloblastic leukaemia; 1/5 patients with chronic myelocytic leukaemia (CML) in blastic crisis; and 2/2 patients with diffuse lymphoblastic lymphoma. In contrast less than 1% of TdT(+) cells were found in 20 marrow or peripheral-blood samples from ALL patients in complete remission; 8 patients with CML in chronic phase; 2 patients with myeloma; 1 sample from a patient with Hodgkin's disease, peripheral-blood samples from 7 normal donors and marrow samples from 6 patients without haematological malignancies. TdT(+) cells were also found in association with cells with lymphoblast morphology. The TdT(+) cells in marrow were shown to be directly correlated with the percentage of morphological lymphoblasts, with a Spearman rank coefficient of 0·81, significant at a 0·001 level. In 2 longitudinal studies of 2 ALL patients with TdT(+) cells at diagnosis, the percentage TdT(+) cells also changed in parallel with the proportion of lymphoblasts. However, studies of 2 other patients with morphologically diagnosed ALL with < 1% TdT(+) cells at diagnosis also showed < 1% TdT(+) cells throughout the period studied, indicating a stable phenotype of blast cells in these patients. The single-cell immunofluorescence assay for TdT, which requires < 0·1% of the cells used in a conventional biochemical assay, is highly specific, and could provide a technically more efficient alternative for use in clinics as well as in experimental investigations of subpopulations of leukaemic and normal marrow cells.

Macrophage Activation Mechanisms in Human Monocytic Cell Line-derived Macrophages.

PubMed

Sumiya, Yu; Ishikawa, Mami; Inoue, Takahiro; Inui, Toshio; Kuchiike, Daisuke; Kubo, Kentaro; Uto, Yoshihiro; Nishikata, Takahito

2015-08-01

Although the mechanisms of macrophage activation are important for cancer immunotherapy, they are poorly understood. Recently, easy and robust assay systems for assessing the macrophage-activating factor (MAF) using monocytic cell line-derived macrophages were established. Gene-expression profiles of U937- and THP-1-derived macrophages were compared using gene expression microarray analysis and their responses against several MAFs were examined by in vitro experiments. Activated states of these macrophages could not be assigned to a specific sub-type but showed, however, different unique characteristics. The unique of monocytic cell line-derived macrophages could provide clues to understand the activation mechanism of macrophages and, therefore, help to develop effective cancer immunotherapy with MAFs. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Increased regulatory T cells in acute lymphoblastic leukaemia patients.

PubMed

Idris, Siti-Zuleha; Hassan, Norfarazieda; Lee, Le-Jie; Md Noor, Sabariah; Osman, Raudhawati; Abdul-Jalil, Marsitah; Nordin, Abdul-Jalil; Abdullah, Maha

2016-05-01

Regulation in adaptive immune response balances a fine line that prevents instigation of self-damage or fall into unresponsiveness permitting abnormal cell growth. Mechanisms that keep this balance in check include regulatory T cells (Tregs). Tregs consist of a small but heterogeneous population, which may be identified by the phenotype, CD3+CD4+CD25+CD127-. The role of Tregs in pathogenesis of cancers is thus far supported by evidence of increased Tregs in various cancers and may contribute to poorer prognosis. Tregs may also be important in acute leukaemias. A review of the literature on Tregs in acute leukaemias was conducted and Tregs were determined in B-cell acute lymphoblastic leukaemias (ALLs). Studies on Tregs in B-cell ALL are few and controversial. We observed a significantly increased percentage of Tregs (mean±SD, 9.72 ± 3.79% vs. 7.05 ± 1.74%; P = 0.047) in the bone marrow/peripheral blood of ALL (n = 17) compared to peripheral blood of normal controls (n = 35). A positive trend between Tregs and age (R = 0.474, P = 0.055, n = 17) implicates this factor of poor prognosis in B-cell ALL. Tregs in cancer are particularly significant in immunotherapy. The manipulation of the immune system to treat cancer has for a long time ignored regulatory mechanisms inducible or in place. In lymphoma studies, tumour-specific mechanisms that are unlike conventional methods in the induction of Tregs have been hypothesized. In addition, tumour-infiltrating Tregs may present different profiles from peripheral blood pictures. Tregs will continue to be dissected to reveal its mysteries and their impact on clinical significance.

RUNX3 is involved in caspase-3-dependent apoptosis induced by a combination of 5-aza-CdR and TSA in leukaemia cell lines.

PubMed

Zhai, Feng-Xian; Liu, Xiang-Fu; Fan, Rui-Fang; Long, Zi-Jie; Fang, Zhi-Gang; Lu, Ying; Zheng, Yong-Jiang; Lin, Dong-Jun

2012-03-01

Epigenetic therapy has had a significant impact on the management of haematologic malignancies. The aim of this study was to assess whether 5-aza-CdR and TSA inhibit the growth of leukaemia cells and induce caspase-3-dependent apoptosis by upregulating RUNX3 expression. K562 and Reh cells were treated with 5-aza-CdR, TSA or both compounds. RT-PCR and Western blot analyses were used to examine the expression of RUNX3 at the mRNA and protein levels, respectively. Immunofluorescence microscopy was used to detect the cellular location of RUNX3. Additionally, after K562 cells were transfected with RUNX3, apoptosis and proliferation were studied using Annexin V staining and MTT assays. The expression of RUNX3 in leukaemia cell lines was markedly less than that in the controls. Demethylating drug 5-aza-CdR could induce RUNX3 expression, but the combination of TSA and 5-aza-CdR had a greater effect than did treatment with a single compound. The combination of 5-aza-CdR and TSA induced the translocation of RUNX3 from the cytoplasm into the nucleus. TSA enhanced apoptosis induced by 5-aza-CdR, and Annexin V and Hoechst 33258 staining showed that the combination induced apoptosis but not necrosis. Furthermore, apoptosis was dependent on the caspase-3 pathway. RUNX3 overexpression in K562 cells led to growth inhibition and apoptosis and potentiated the effects of 5-aza-CdR induction. RUNX3 plays an important role in leukaemia cellular functions, and the induction of RUNX3-mediated effects may contribute to the therapeutic value of combination TSA and 5-aza-CdR treatment.

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

PubMed Central

2012-01-01

Background 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. Methods 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. Results 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. Conclusions 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. PMID:23217014

Effects of pharmacological and genetic disruption of CXCR4 chemokine receptor function in B-cell acute lymphoblastic leukaemia.

PubMed

Randhawa, Shubhchintan; Cho, Byung S; Ghosh, Dipanjan; Sivina, Mariela; Koehrer, Stefan; Müschen, Markus; Peled, Amnon; Davis, Richard E; Konopleva, Marina; Burger, Jan A

2016-08-01

B cell acute lymphoblastic leukaemia (B-ALL) cells express high levels of CXCR4 chemokine receptors for homing and retention within the marrow microenvironment. Bone marrow stromal cells (BMSC) secrete CXCL12, the ligand for CXCR4, and protect B-ALL cells from cytotoxic drugs. Therefore, the therapeutic use of CXCR4 antagonists has been proposed to disrupt cross talk between B-ALL cells and the protective stroma. Because CXCR4 antagonists can have activating agonistic function, we compared the genetic and pharmacological deletion of CXCR4 in B-ALL cells, using CRISPR-Cas9 gene editing and CXCR4 antagonists that are in clinical use (plerixafor, BKT140). Both genetic and pharmacological CXCR4 inhibition significantly reduced B-ALL cell migration to CXCL12 gradients and beneath BMSC, and restored drug sensitivity to dexamethasone, vincristine and cyclophosphamide. NOD/SCID/IL-2rγnull mice injected with CXCR4 gene-deleted B-ALL cells had significant delay in disease progression and superior survival when compared to control mice injected with CXCR4 wild-type B-ALL cells. These findings indicate that anti-leukaemia activity of CXCR4 antagonists is primarily due to CXCR4 inhibition, rather than agonistic activity, and corroborate that CXCR4 is an important target to overcome stroma-mediated drug resistance in B-ALL. © 2016 John Wiley & Sons Ltd.

Atypical chronic myeloid leukaemia: A case of an orphan disease-A multicenter report by the Polish Adult Leukemia Group.

PubMed

Drozd-Sokołowska, Joanna; Mądry, Krzysztof; Waszczuk-Gajda, Anna; Biecek, Przemysław; Szwedyk, Paweł; Budziszewska, Katarzyna; Raźny, Magdalena; Dutka, Magdalena; Obara, Agata; Wasilewska, Ewa; Lewandowski, Krzysztof; Piekarska, Agnieszka; Bober, Grażyna; Krzemień, Helena; Stella-Hołowiecka, Beata; Kapelko-Słowik, Katarzyna; Sawicki, Waldemar; Paszkowska-Kowalewska, Małgorzata; Machowicz, Rafał; Dwilewicz-Trojaczek, Jadwiga

2018-03-07

Atypical chronic myeloid leukaemia (aCML) belongs to myelodysplastic/myeloproliferative neoplasms. Because of its rarity and changing diagnostic criteria throughout subsequent classifications, data on aCML are very scarce. Therefore, we at the Polish Adult Leukemia Group performed a nationwide survey on aCML. Eleven biggest Polish centres participated in the study. Altogether, 45 patients were reported, among whom only 18 patients (40%) fulfilled diagnostic criteria. Among misdiagnosed patients, myelodysplastic/myeloproliferative syndrome unclassifiable and chronic myelomonocytic leukaemia were the most frequent diagnoses. Thirteen patients were male, median age 64.6 years (range 40.4-80.9). The median parameters at diagnosis were as follows: white blood cell count 97 × 10 9 /L (23.8-342) with immature progenitors amounting at 27.5% (12-72), haemoglobin 8.6 g/dL (3.9-14.9), and platelet count 66 × 10 9 /L (34-833). Cytoreductive treatment was used in all patients, and 2 patients underwent allogeneic hematopoietic stem cell transplantation. The median overall survival was 14.1 months (95% CI, 7.2), with median acute myeloid leukaemia-free survival of 13.3 months (95% CI, 3.6-22.6). Cumulative incidence of acute myeloid leukaemia transformation after 1 year in aCML group was 12.5% (95% CI, 0%-29.6%). To conclude, aCML harbours a poor prognosis. Treatment options are limited, with allogeneic hematopoietic stem cell transplantation being the only curative method at present, although only a minority of patients are transplant eligible. Educational measures are needed to improve the quality of diagnoses. Copyright © 2018 John Wiley & Sons, Ltd.

The regulated in development and DNA damage response 2 (REDD2) gene mediates human monocyte cell death through a reduction in thioredoxin-1 expression.

PubMed

Imen, Jguirim-Souissi; Billiet, Ludivine; Cuaz-Pérolin, Clarisse; Michaud, Nadège; Rouis, Mustapha

2009-05-15

In a previous study, we identified the regulated in development and DNA damage response 2 (REDD2) gene as a highly expressed gene in human atherosclerotic lesions in comparison to normal artery, as well as in cultured human macrophages, and showed its implication in oxidized low-density lipoprotein (LDL)-induced macrophage death sensitivity. In this article, we attempt to identify the mechanism by which REDD2 induces such a phenomenon. Transient transfection of U-937 monocytic cells with a pCI.CMV.REDD2 expression vector increased by approximately twofold the mRNA levels of REDD2 in comparison to control cells transfected with pCI.CMV.GFP. Reactive oxygen species (ROS) production was significantly induced in REDD2-transfected cells compared with control cells (157+/-48 and 100+/-8 arbitrary units/mg cell protein, respectively; p<0.05). Moreover, a significant increase in parameters known to reflect the oxidative modifications of LDL was observed. Among enzymes involved in ROS production or degradation, we found a specific reduction in thioredoxin-1 (Trx-1) mRNA ( approximately 52+/-7% decrease, p<0.01 vs control cells) and protein ( approximately 60+/-4% decrease, p<0.001 vs control cells) levels in cells overexpressing REDD2 in comparison to control cells. In contrast, transfection of U-937 cells with siRNA against REDD2 decreased the mRNA levels of REDD2 by approximately 60% and increased Trx-1 mRNA and protein levels. Moreover, we observed no or a moderate increase in Bax (proapoptotic) and a significant decrease in Bcl2 (antiapoptotic) gene expression in cells that overexpress REDD2 compared to control cells. In addition, we showed that Trx-1 mRNA and protein levels were increased at low H(2)O(2) doses and decreased at higher doses. Interestingly, macrophages isolated from human atherosclerotic lesions differentially express REDD2 and Trx-1. Indeed, in certain patients, levels of REDD2 mRNA were low and those of Trx-1 mRNA were high. In contrast, in other patients, levels of REDD2 were high and levels of Trx-1 mRNA were low.

Oncogenic Nras has bimodal effects on stem cells that sustainably increase competitiveness.

PubMed

Li, Qing; Bohin, Natacha; Wen, Tiffany; Ng, Victor; Magee, Jeffrey; Chen, Shann-Ching; Shannon, Kevin; Morrison, Sean J

2013-12-05

'Pre-leukaemic' mutations are thought to promote clonal expansion of haematopoietic stem cells (HSCs) by increasing self-renewal and competitiveness; however, mutations that increase HSC proliferation tend to reduce competitiveness and self-renewal potential, raising the question of how a mutant HSC can sustainably outcompete wild-type HSCs. Activating mutations in NRAS are prevalent in human myeloproliferative neoplasms and leukaemia. Here we show that a single allele of oncogenic Nras(G12D) increases HSC proliferation but also increases reconstituting and self-renewal potential upon serial transplantation in irradiated mice, all prior to leukaemia initiation. Nras(G12D) also confers long-term self-renewal potential to multipotent progenitors. To explore the mechanism by which Nras(G12D) promotes HSC proliferation and self-renewal, we assessed cell-cycle kinetics using H2B-GFP label retention and 5-bromodeoxyuridine (BrdU) incorporation. Nras(G12D) had a bimodal effect on HSCs, increasing the frequency with which some HSCs divide and reducing the frequency with which others divide. This mirrored bimodal effects on reconstituting potential, as rarely dividing Nras(G12D) HSCs outcompeted wild-type HSCs, whereas frequently dividing Nras(G12D) HSCs did not. Nras(G12D) caused these effects by promoting STAT5 signalling, inducing different transcriptional responses in different subsets of HSCs. One signal can therefore increase HSC proliferation, competitiveness and self-renewal through bimodal effects on HSC gene expression, cycling and reconstituting potential.

Ultraviolet (UV)-Curable Coatings for Aerospace Applications

DTIC Science & Technology

2012-08-31

OF RESPONSIBLE PERSON Dave Madden a. REPORT U b. ABSTRACT U c . THIS PAGE U UU 259 19b. TELEPHONE NUMBER (include area code) (937) 656-5709...127 Appendix C - DSM Desotech Month by Month Progress...17 Figure 6. Black Topcoat Cured on 911th Airlift Wing C -130.......................................18 Figure 7. Black Topcoat Cured on C

Lysozyme activity and nitroblue-tetrazolium reduction in leukaemic cells

PubMed Central

Catovsky, D.; Galton, D. A. G.

1973-01-01

The cytochemical methods for lysozyme and nitroblue-tetrazolium reduction have been used to study the blast cells of acute myeloid leukaemia. Both proved useful in characterizing the cases with predominant monocytic differentiation. The demonstration of lysozyme activity helped to define two main groups: (a) with predominantly lysozyme-negative cells (myeloblastic-promyelocytic), and (b) with considerable numbers of positive cells (monoblastic-monocytic). In addition this test was also of value in the differentiation of other leukaemic disorders. Reduction of nitroblue-tetrazolium was also a feature of monocytic differentiation. The combination of these two methods with those for myeloperoxidase and non-specific esterase activity contributes to the cytological characterization of acute myeloid leukaemia. Images PMID:4511938

Acute myeloid leukaemia diagnosed by intra-oral myeloid sarcoma. A case report.

PubMed

Papamanthos, Mattheos K; Kolokotronis, Alexandros E; Skulakis, Haralampos E; Fericean, Angela-Monika A; Zorba, Matina T; Matiakis, Apostolos T

2010-06-01

Myeloid sarcoma (MS) is a rare extramedullary malignant tumor composed of immature myeloid cells. It is strongly associated with a well known or covert acute myeloid leukaemia, chronic myeloproliferative diseases or myelodysplastic syndromes. Intraoral MS scarcely occurs. An unusual case of acute myeloid leukaemia, which was diagnosed by mandibular MS that was developed in the alveolar socket after a dental extraction, is reported. The histological examination (including immunohistochemical analysis) of a subsequent biopsy showed infiltration of the oral mucosa by neoplastic cells. This lesion was therefore classified as acute myeloid leukaemia. The patient was referred to oncologists that confirmed the initial diagnosis. The patient underwent chemotherapy and the mandibular tumor disappeared. Forty days later, a relapse of the disease, which appeared as a great-ulcerated lesion, was developed in the hard palate. Thirty days after the second chemotherapy had finished, a new intraoral tumor was developed in the vestibular maxillary gingiva. Review of the literature shows no report of intraoral relapse and particularly multiple relapse of a MS that involves the oral cavity. Even though MS is encountered infrequently in the oral cavity, it should be considered in the differential diagnosis of conditions (especially tumors) with a similar clinical appearance.

Acute Myeloid Leukaemia Diagnosed by Intra-Oral Myeloid Sarcoma. A Case Report

PubMed Central

Papamanthos, Mattheos K.; Skulakis, Haralampos E.; Fericean, Angela-Monika A.; Zorba, Matina T.; Matiakis, Apostolos T.

2010-01-01

Myeloid sarcoma (MS) is a rare extramedullary malignant tumor composed of immature myeloid cells. It is strongly associated with a well known or covert acute myeloid leukaemia, chronic myeloproliferative diseases or myelodysplastic syndromes. Intraoral MS scarcely occurs. An unusual case of acute myeloid leukaemia, which was diagnosed by mandibular MS that was developed in the alveolar socket after a dental extraction, is reported. The histological examination (including immunohistochemical analysis) of a subsequent biopsy showed infiltration of the oral mucosa by neoplastic cells. This lesion was therefore classified as acute myeloid leukaemia. The patient was referred to oncologists that confirmed the initial diagnosis. The patient underwent chemotherapy and the mandibular tumor disappeared. Forty days later, a relapse of the disease, which appeared as a great-ulcerated lesion, was developed in the hard palate. Thirty days after the second chemotherapy had finished, a new intraoral tumor was developed in the vestibular maxillary gingiva. Review of the literature shows no report of intraoral relapse and particularly multiple relapse of a MS that involves the oral cavity. Even though MS is encountered infrequently in the oral cavity, it should be considered in the differential diagnosis of conditions (especially tumors) with a similar clinical appearance. PMID:20512638

Evolving prevalence of haematological malignancies in orphan designation procedures in the European Union.

PubMed

Polsinelli, Benedetta; Tsigkos, Stelios; Naumann-Winter, Frauke; Mariz, Segundo; Sepodes, Bruno

2017-01-21

The Committee for Orphan Medicinal Products (COMP) evaluates prevalence of rare conditions as one of the criteria for granting an orphan designation with a prevalence threshold of 5 in 10.000. At the time of Marketing Authorisation (MA) these criteria are reassessed to ensure they are still met. The COMP has noted discordance between the prevalence of certain haematological malignancies at the time of Orphan Designation and at the time of Marketing Authorisation. Consequently, we conducted a retrospective assessment of Chronic Lymphocytic Lymphoma and Multiple Myeloma/Plasma cell Myeloma as well as several other haematological rare aetiologies frequently subject of orphan designation. These were: Diffuse large B-Cell Lymphoma (DLBCL), Follicular Lymphoma (FL), Cutaneous T-Cell Lymphoma (CTCL), Mantle Cell Lymphoma (MCL) and Chronic Myeloid Leukaemia (CML). The review used submissions as well as recent publications and results from external and EMA databases. As a first step in the analysis, an increase over time in the number of people affected was evident for four conditions in the COMP designation documents, whereas for DLBCL, FL, CTCL and MCL there had been no significant change, since the introduction of the Regulation in 2000. Specifically, the prevalence estimates increased from 1.2 to 3.6 per 10,000 for multiple myeloma, from 0.4 to 1.7 in acute lymphoblastic leukaemia, and from 2.7 to 4.85 for chronic lymphocytic leukaemia/small lymphocytic leukaemia and 1 to 2 in 10,000 for chronic myeloid leukaemia. The reasons for the changes in the prevalence of these four haematological conditions over the last 15 years were not assessed but recent publications have alluded to better outcomes due to new treatments being made available. In addition, many orphan diseases have a median age of onset over 60 years so that also the aging of the population may be a relevant contributing factor.

Ibrutinib (Imbruvica). Relapsed chronic lymphocytic leukaemia and mantle cell lymphoma: uncertain impact on survival.

PubMed

January

2016-04-01

codynamic interactions are also likely in view of its adverse effect profile. There is no consensus on the treatment of patients with refractory or relapsed mantle cell lymphoma, or for patients with relapsed or possibly refractory chronic lymphocytic leukaemia. Ibrutinib inhibits an enzyme involved in regulating B lymphocyte activity. It has been authorised in the European Union for these conditions. Clinical evaluation of ibrutinib in mantle cell lymphoma is based on a single non-comparative trial in 111 patients, in which the median overall survival time was 22.5 months. Clinical evaluation of ibrutinib in chronic lymphocytic leukaemia is based on two randomised trials. One unblinded trial compared ibrutinib versus ofatumumab and involved 391 patients, most of whom were sufficiently fit to receive anticancer combination therapy. Ibrutinib was more effective than ofatumumab, but the choice of this comparator might not have been appropriate for most of the patients who received it. The other double-blind, placebo-controlled trial involved 578 patients with relapsed or refractory chronic lymphocytic leukaemia. Ibrutinib was added to the bendamustine + rituximab combination. No significant difference in mortality was observed between the two groups. The main adverse effects of ibrutinib were: gastrointestinal disorders such as diarrhoea; life-threatening infections and bleeding disorders; and cardiac disorders, including atrial fibrillation. Ibrutinib carries a risk of multiple pharmacokinetic interactions. Pharmacodynamic interactions are also likely in view of its adverse effect profile.

Preventing relapse after haematopoietic stem cell transplantation for acute leukaemia: the role of post-transplantation minimal residual disease (MRD) monitoring and MRD-directed intervention.

PubMed

Mo, Xiao-Dong; Lv, Meng; Huang, Xiao-Jun

2017-10-01

Relapse is the main cause of treatment failure after allogeneic haematopoietic stem cell transplantation (allo-HSCT) for acute leukaemia (AL). Post-transplantation minimal residual disease (MRD) monitoring enables risk stratification and identifies AL patients at higher risk of relapse. MRD assessment primarily involves the determination of leukaemia-associated immunophenotypic patterns using multiparameter flow cytometry, and the polymerase chain reaction (PCR)-based evaluation of expression levels of leukaemia-related genes (specific reciprocal gene rearrangements and other mutation types). In addition, next generation sequencing and digital PCR may further enrich current MRD detection. Several MRD-directed interventions have demonstrated the ability to reduce the risk of relapse with acceptable treatment-related toxicities. Donor lymphocyte infusion (DLI) is the most important intervention for MRD-positive patients, while several modified strategies, such as granulocyte colony-stimulating factor-mobilized peripheral blood cells followed by short term immune suppression and escalating dose regimen, further improve the safety and efficacy of DLI. Interferon therapy, targeted drugs, and hypomethylating agents have also been introduced for MRD-directed interventions. Referring to the issues of whether and who would benefit from pre-emptive intervention according to MRD, in this review, we summarized this rapidly evolving area of MRD monitoring and MRD-directed interventions in AL patients after allo-HSCT. © 2017 John Wiley & Sons Ltd.

The development of a three-dimensional scaffold for ex vivo biomimicry of human acute myeloid leukaemia.

PubMed

Blanco, Teresa Mortera; Mantalaris, Athanasios; Bismarck, Alexander; Panoskaltsis, Nicki

2010-03-01

Acute myeloid leukaemia (AML) is a cancer of haematopoietic cells that develops in three-dimensional (3-D) bone marrow niches in vivo. The study of AML has been hampered by lack of appropriate ex vivo models that mimic this microenvironment. We hypothesised that fabrication and optimisation of suitable biomimetic scaffolds for culturing leukaemic cells ex vivo might facilitate the study of AML in its native 3-D niche. We evaluated the growth of three leukaemia subtype-specific cell lines, K-562, HL60 and Kasumi-6, on highly porous scaffolds fabricated from biodegradable and non-biodegradable polymeric materials, such as poly (L-lactic-co-glycolic acid) (PLGA), polyurethane (PU), poly (methyl-methacrylate), poly (D, L-lactade), poly (caprolactone), and polystyrene. Our results show that PLGA and PU supported the best seeding efficiency and leukaemic growth. Furthermore, the PLGA and PU scaffolds were coated with extracellular matrix (ECM) proteins, collagen type I (62.5 or 125 microg/ml) and fibronectin (25 or 50 microg/ml) to provide biorecognition signals. The 3 leukaemia subtype-specific lines grew best on PU scaffolds coated with 62.5 microg/ml collagen type I over 6 weeks in the absence of exogenous growth factors. In conclusion, PU-collagen scaffolds may provide a practical model to study the biology and treatment of primary AML in an ex vivo mimicry. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

[Synthetic transformations of higher terpenoids. XXX. Synthesis and cytotoxic activity of betulonic acid amides with a piperidine or pyrrolidine nitroxide moiety].

PubMed

Antimonova, A N; Petrenko, N I; Shults, E E; Polienko, Iu F; Shakirov, M M; Irtegova, I G; Pokrovskiĭ, M A; Sherman, K M; Grigor'ev, I A; Pokrovskiĭ, A G; Tolstikov, G A

2013-01-01

The reaction of betulonic acid chloride with 4-amino-2,2,6,6-tetramethylpeperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl gave corresponding triterpenoid amides. It was found that new derivatives exhibit cytotoxic activity against tumor cells CEM-13, U-937, MT-4. CCID50 value for most activity compound--N-[3-oxolup-20(29)-en-30-yl]-(2,2,6,6-tetramethylpiperidine-4-yl)-1-oxyl--was 5.7-33.1 microM.

[Apoptosis of human leukemic cells induced by topoisomerase I and II inhibitors].

PubMed

Solary, E; Dubrez, L; Eymin, B; Bertrand, R; Pommier, Y

1996-03-01

Comparison between five human leukemic lines (BV173, HL60, U937, K562, KCL22) suggest that the main determinant of their sensitivity to topoisomerase I (camptothecin) and II (VP-16) inhibitors is their ability to regulate cell cycle progression in response to specific DNA damage, then to die through apoptosis: the more the cells inhibit cell cycle progression, the less sensitive they are. The final pathway of apoptosis induction involves a cytoplasmic signal, active at neutral pH, needing magnesium, sensitive to various protease inhibitors and activated directly by staurosporine. Modulators of intracellular signaling (calcium chelators, calmodulin inhibitors, PKC modulators, kinase and phosphatase inhibitors) have no significant influence upon apoptosis induction. Conversely, apoptosis induction pathway is modified during monocytic differentiation of HL60 cells induced by phorbol esters. Lastly, poly(ADP-ribosyl)ation and chromatine structure should regulate apoptotic DNA fragmentation that is prevented by 3-aminobenzamide and spermine, respectively.

Suppressive Effect of Hydroquinone, a Benzene Metabolite, on In Vitro Inflammatory Responses Mediated by Macrophages, Monocytes, and Lymphocytes

PubMed Central

Cho, Jae Youl

2008-01-01

We investigated the inhibitory effects of hydroquinone on cytokine release, phagocytosis, NO production, ROS generation, cell-cell/cell fibronectin adhesion, and lymphocyte proliferation. We found that hydroquinone suppressed the production of proinflammatory cytokines [tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6], secretion of toxic molecules [nitric oxide (NO) and reactive oxygen species (ROS)], phagocytic uptake of FITC-labeled dextran, upregulation of costimulatory molecules, U937 cell-cell adhesion induced by CD18 and CD29, and the proliferation of lymphocytes from the bone marrow and spleen. Considering that (1) environmental chemical stressors reduce the immune response of chronic cigarette smokers and children against bacterial and viral infections and that (2) workers in petroleum factories are at higher risk for cancer, our data suggest that hydroquinone might pathologically inhibit inflammatory responses mediated by monocytes, macrophages, and lymphocytes. PMID:19148301

[Platelet function in acute myeloid leukemia. II. Aggregation of isolated platelets].

PubMed

Zawilska, K; Komarnicki, M; Mańka, B

1978-01-01

In 22 patients with acute myeloid leukaemia (17 cases of myeloblastic leukaemia, 4 cases of myelomonocytic leukaemia and 1 case of undifferentiated-cell leukaemia) platelets were isolated from the plasma by the method of Nicholls and Hampton as modified by Levy-Toledano by centrifugation in albumin gradient. The aim of platelet isolation was their "concentration" in cases of thrombocytopenia to values making possible aggregation tests, and platelet separation from the influence of plasma factors. Then aggregation of isolated platelets caused by ADP was studied. In 16 out of 22 patients a fall of aggregation was observed, with the mean values of aggregation rate and intensity were significantly lower. Parallelly done determinations of aggregating activity released from the platelets by thrombin showed lower values as compared with platelets from healthy subjects. In might be thought, in this connection, that the demonstrated reduction of isolated platelets is associated with a diminution of the nucleotide pool or disturbances of the platelet release reaction. The disturbances of the platelet release reaction. The disturbances of aggregation of isolated platelets and reduction of the aggregating activity were most pronounced in acute myelomonocytic leukaemia.

Role of BAFF and APRIL in human B-cell chronic lymphocytic leukaemia

PubMed Central

Haiat, Stéphanie; Billard, Christian; Quiney, Claire; Ajchenbaum-Cymbalista, Florence; Kolb, Jean-Pierre

2006-01-01

B-cell chronic lymphocytic leukaemia (B-CLL) is the most prevalent leukaemia in Western countries and is characterized by the gradual accumulation in patients of small mature B cells. Since the vast majority of tumoral cells are quiescent, the accumulation mostly results from deficient apoptosis rather than from acute proliferation. Although the phenomenon is relevant in vivo, B-CLL cells die rapidly in vitro as a consequence of apoptosis, suggesting a lack of essential growth factors in the culture medium. Indeed, the rate of B-CLL cell death in vitro is modulated by different cytokines, some favouring the apoptotic process, others counteracting it. Two related members of the tumour necrosis factor family, BAFF (B-cell activating factor of the TNF family) and APRIL (a proliferation-inducing ligand), already known for their crucial role in normal B-cell survival, differentiation and apoptosis, were recently shown to be expressed by B-CLL cells. These molecules are able to protect the leukaemic cells against spontaneous and drug-induced apoptosis via autocrine and/or paracrine pathways. This review will focus on the role of BAFF and APRIL in the survival of tumoral cells. It will discuss the expression of these molecules by B-CLL cells, their regulation, transduction pathways and their effects on leukaemic cells. The design of reagents able to counteract the effects of these molecules seems to be a new promising therapeutic approach for B-CLL and is already currently developed in the treatment of autoimmune diseases. PMID:16827889

A case-control study to investigate the association between exposure to benzene and deaths from leukaemia in oil refinery workers.

PubMed

Rushton, L; Alderson, M R

1981-01-01

All deaths with a mention of leukaemia on the death certificate, in men employed over a period of 25 years of 8 oil refineries in the U.K. were identified. The potential benzene exposure of these cases was compared with that of two sets of controls selected from the total refinery population. One set of controls was matched for refinery and year of birth, the other set was matched for refinery, year of birth nd length of service. No information was available on measurement of benzene in the work environment but a job history was obtained from refinery personnel records for all cases and controls. This was used to allocate each man to a benzene exposure level of "low", "medium", or "high". There was no overall excess of deaths from leukaemia when compared with the expectation from national rates. There was also no excess of cytological types of leukaemia which have been shown to be particularly associated with benzene exposure. However, the risk for those men with medium or high exposure relative to the risk for those with low benzene exposure approached a significance (P=0.05) when length of service was taken into account. If there were an increased risk of leukaemia due to benzene exposure, it could have only been one that affected a very small proportion of men within the refinery workforce.

Durable graft-versus-leukaemia effects without donor lymphocyte infusions - results of a phase II study of sequential T-replete allogeneic transplantation for high-risk acute myeloid leukaemia and myelodysplasia.

PubMed

Davies, Jeff K; Hassan, Sandra; Sarker, Shah-Jalal; Besley, Caroline; Oakervee, Heather; Smith, Matthew; Taussig, David; Gribben, John G; Cavenagh, Jamie D

2018-02-01

Allogeneic haematopoietic stem-cell transplantation remains the only curative treatment for relapsed/refractory acute myeloid leukaemia (AML) and high-risk myelodysplasia but has previously been limited to patients who achieve remission before transplant. New sequential approaches employing T-cell depleted transplantation directly after chemotherapy show promise but are burdened by viral infection and require donor lymphocyte infusions (DLI) to augment donor chimerism and graft-versus-leukaemia effects. T-replete transplantation in sequential approaches could reduce both viral infection and DLI usage. We therefore performed a single-arm prospective Phase II clinical trial of sequential chemotherapy and T-replete transplantation using reduced-intensity conditioning without planned DLI. The primary endpoint was overall survival. Forty-seven patients with relapsed/refractory AML or high-risk myelodysplasia were enrolled; 43 proceeded to transplantation. High levels of donor chimerism were achieved spontaneously with no DLI. Overall survival of transplanted patients was 45% and 33% at 1 and 3 years. Only one patient developed cytomegalovirus disease. Cumulative incidences of treatment-related mortality and relapse were 35% and 20% at 1 year. Patients with relapsed AML and myelodysplasia had the most favourable outcomes. Late-onset graft-versus-host disease protected against relapse. In conclusion, a T-replete sequential transplantation using reduced-intensity conditioning is feasible for relapsed/refractory AML and myelodysplasia and can deliver graft-versus-leukaemia effects without DLI. © 2017 John Wiley & Sons Ltd.

Hyperleukocytosis and leukocytapheresis in acute leukaemias: experience from a single centre and review of the literature of leukocytapheresis in acute myeloid leukaemia.

PubMed

Bruserud, Ø; Liseth, K; Stamnesfet, S; Cacic, D L; Melve, G; Kristoffersen, E; Hervig, T; Reikvam, H

2013-12-01

Hyperleukocytosis is usually defined as leukocyte count >100 × 10(9)  L(-1) and can be seen in newly diagnosed leukaemias. Hyperleukocytic leukaemia is associated with a risk of organ failure and early death secondary to leukostasis. Mechanical removal of leukocytes by the apheresis technique, leukocytapheresis, is a therapeutic option in these patients. During a 16-year period, 16 patients were treated with leukocytapheresis (35 apheresis procedures) for hyperleukocytosis/leukostasis. We present our experience, and in addition we review previous studies of hyperleukocytosis/leukocytapheresis in patients with acute myeloid leukaemia (AML). We used a highly standardised approach for leukocytapheresis in leukaemia patients with hyperleukocytosis. The average leukocytapheresis number for each patient was 2·2 (range 1-6). Median leukocyte count before apheresis was 309 × 10(9)  L(-1) (range 104-935); the mean leukocyte count reduction was 71%, corresponding to a mean absolute reduction of 219 × 10(9)  L(-1). No serious side effects were seen during or immediately after apheresis. The data suggest that our standardised technique for leukocytapheresis effectively reduced the peripheral blood leukaemia cell counts. Previous studies in AML also support the conclusion that this is a safe and effective procedure for the treatment of a potentially life-threatening complication, but apheresis should always be combined with early chemotherapy. © 2013 The Authors. Transfusion Medicine © 2013 British Blood Transfusion Society.

T cell chronic lymphocytic leukaemia with suppressor phenotype.

PubMed Central

Hofman, F M; Smith, D; Hocking, W

1982-01-01

The peripheral blood cells from a patient with T cell chronic lymphocytic leukaemia were examined for surface marker and functional characteristics. Eighty-91% of the peripheral blood cells formed SRBC rosettes and 22-49% possessed Fc receptors; 73% of the peripheral blood cells were reactive with the OKT8 antiserum and 61% expressed DR antigens. Response to PHA stimulation was markedly reduced, whereas allogeneic responsiveness in mixed leucocyte culture was intact. The ability of Con A-stimulated peripheral blood cells to generate suppressor activity in a mixed leucocyte reaction was deficient, whereas suppression of in vitro immunoglobulin synthesis was greater than normal. The leukaemic peripheral blood cell population expressed a T suppressor phenotype. Functional studies suggest that these cells were derived from the subset of T lymphocytes with regulatory activity for immunoglobulin synthesis as opposed to mitogenic responsiveness. PMID:6215199

Ectopic overexpression of LAPTM5 results in lysosomal targeting and induces Mcl-1 down-regulation, Bak activation, and mitochondria-dependent apoptosis in human HeLa cells

PubMed Central

Jun, Do Youn; Kim, Hyejin; Jang, Won Young; Lee, Ji Young; Fukui, Kiyoshi; Kim, Young Ho

2017-01-01

Human lysosomal-associated protein multispanning membrane 5 (LAPTM5) was identified by an ordered differential display-polymerase chain reaction (ODD-PCR) as an up-regulated cDNA fragment during 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced differentiation of U937 cells into monocytes/macrophages. After TPA-treatment, the levels of LAPTM5 mRNA and protein increased and reached a maximum at 18–36 h. In healthy human tissues, LAPTM5 mRNA was expressed at high levels in hematopoietic cells and tissues, at low levels in the lung and fetal liver, and was not detected in other non-hematopoietic tissues. LAPTM5 mRNA was detected in immature malignant cells of myeloid lineage, such as K562, HL-60, U937, and THP-1 cells, and in unstimulated peripheral T cells, but was absent or barely detectable in lymphoid malignant or non-hematopoietic malignant cells. The LAPTM5 level in HL-60 cells increased more significantly during TPA-induced monocyte/macrophage differentiation than during DMSO-induced granulocyte differentiation. Ectopic expression of GFP-LAPTM5 or LAPTM5 in HeLa cells exhibited the localization of LAPTM5 to the lysosome. In HeLa cells overexpressing LAPTM5, the Mcl-1 and Bid levels declined markedly and apoptosis was induced via Bak activation, Δψm loss, activation of caspase-9, -8 and -3, and PARP degradation without accompanying necrosis. However, these LAPTM5-induced apoptotic events except for the decline of Bid level were completely abrogated by concomitant overexpression of Mcl-1. The pan-caspase inhibitor (z-VAD-fmk) could suppress the LAPTM5-induced apoptotic sub-G1 peak by ~40% but failed to block the induced Δψm loss, whereas the broad-range inhibitor of cathepsins (Cathepsin Inhibitor I) could suppress the LAPTM5-induced apoptotic sub-G1 peak and Δψm loss, by ~22% and ~23%, respectively, suggesting that the LAPTM5-mediated Δψm loss was exerted at least in part in a cathepsin-dependent manner. Together, these results demonstrate that ectopic overexpression of LAPTM5 in HeLa cells induced apoptosis via cleavage of Mcl-1 and Bid by a LAPTM5-associated lysosomal pathway, and subsequent activation of the mitochondria-dependent caspase cascade. PMID:28464033

TLR3 Ligand Poly(I:C) Exerts Distinct Actions in Synovial Fibroblasts When Delivered by Extracellular Vesicles

PubMed Central

Frank-Bertoncelj, Mojca; Pisetsky, David S.; Kolling, Christoph; Michel, Beat A.; Gay, Renate E.; Jüngel, Astrid; Gay, Steffen

2018-01-01

Extracellular vesicles (EV) can modulate the responses of cells to toll-like receptor (TLR) ligation; conversely, TLR ligands such as double-stranded RNA (dsRNA) can enhance the release of EV and influence of the composition and functions of EV cargos. Inflamed synovial joints in rheumatoid arthritis (RA) are rich in EV and extracellular RNA; besides, RNA released from necrotic synovial fluid cells can activate the TLR3 signaling in synovial fibroblasts (SFs) from patients with RA. Since EV occur prominently in synovial joints in RA and may contribute to the pathogenesis, we questioned whether EV can interact with dsRNA, a TLR3 ligand, and modify its actions in arthritis. We have used as model the effects on RA SFs, of EV released from monocyte U937 cells and peripheral blood mononuclear cells upon stimulation with Poly(I:C), a synthetic analog of dsRNA. We show that EV released from unstimulated cells and Poly(I:C)-stimulated U937 cells [Poly(I:C) EV] differ in size but bind similar amounts of Annexin V and express comparable levels of MAC-1, the receptor for dsRNA, on the vesicular membranes. Specifically, Poly(I:C) EV contain or associate with Poly(I:C) and at least partially protect Poly(I:C) from RNAse III degradation. Poly(I:C) EV shuttle Poly(I:C) to SFs and reproduce the proinflammatory and antiviral gene responses of SFs to direct stimulation with Poly(I:C). Poly(I:C) EV, however, halt the death receptor-induced apoptosis in SFs, thereby inverting the proapoptotic nature of Poly(I:C). These prosurvival effects sharply contrast with the high toxicity of cationic liposome-delivered Poly(I:C) and may reflect the route of Poly(I:C) delivery via EV or the fine-tuning of Poly(I:C) actions by molecular cargo in EV. The demonstration that EV may safeguard extracellular dsRNA and allow dsRNA to exert antiapoptotic effects on SFs highlights the potential of EV to amplify the pathogenicity of dsRNA in arthritis beyond inflammation (by concurrently enhancing the expansion of the invasive synovial stroma). PMID:29434584

DNA-damage-induced differentiation of leukaemic cells as an anti-cancer barrier.

PubMed

Santos, Margarida A; Faryabi, Robert B; Ergen, Aysegul V; Day, Amanda M; Malhowski, Amy; Canela, Andres; Onozawa, Masahiro; Lee, Ji-Eun; Callen, Elsa; Gutierrez-Martinez, Paula; Chen, Hua-Tang; Wong, Nancy; Finkel, Nadia; Deshpande, Aniruddha; Sharrow, Susan; Rossi, Derrick J; Ito, Keisuke; Ge, Kai; Aplan, Peter D; Armstrong, Scott A; Nussenzweig, André

2014-10-02

Self-renewal is the hallmark feature both of normal stem cells and cancer stem cells. Since the regenerative capacity of normal haematopoietic stem cells is limited by the accumulation of reactive oxygen species and DNA double-strand breaks, we speculated that DNA damage might also constrain leukaemic self-renewal and malignant haematopoiesis. Here we show that the histone methyl-transferase MLL4, a suppressor of B-cell lymphoma, is required for stem-cell activity and an aggressive form of acute myeloid leukaemia harbouring the MLL-AF9 oncogene. Deletion of MLL4 enhances myelopoiesis and myeloid differentiation of leukaemic blasts, which protects mice from death related to acute myeloid leukaemia. MLL4 exerts its function by regulating transcriptional programs associated with the antioxidant response. Addition of reactive oxygen species scavengers or ectopic expression of FOXO3 protects MLL4(-/-) MLL-AF9 cells from DNA damage and inhibits myeloid maturation. Similar to MLL4 deficiency, loss of ATM or BRCA1 sensitizes transformed cells to differentiation, suggesting that myeloid differentiation is promoted by loss of genome integrity. Indeed, we show that restriction-enzyme-induced double-strand breaks are sufficient to induce differentiation of MLL-AF9 blasts, which requires cyclin-dependent kinase inhibitor p21(Cip1) (Cdkn1a) activity. In summary, we have uncovered an unexpected tumour-promoting role of genome guardians in enforcing the oncogene-induced differentiation blockade in acute myeloid leukaemia.

Sequential chemotherapy followed by reduced-intensity conditioning and allogeneic haematopoietic stem cell transplantation in adult patients with relapse or refractory acute myeloid leukaemia: a survey from the Acute Leukaemia Working Party of EBMT.

PubMed

Ringdén, Olle; Labopin, Myriam; Schmid, Christoph; Sadeghi, Behnam; Polge, Emmanuelle; Tischer, Johanna; Ganser, Arnold; Michallet, Mauricette; Kanz, Lothar; Schwerdtfeger, Rainer; Nagler, Arnon; Mohty, Mohamad

2017-02-01

This study analysed the outcome of 267 patients with relapse/refractory acute myeloid leukaemia (AML) who received sequential chemotherapy including fludarabine, cytarabine and amsacrine followed by reduced-intensity conditioning (RIC) and allogeneic haematopoietic stem cell transplantation (HSCT). The transplants in 77 patients were from matched sibling donors (MSDs) and those in 190 patients were from matched unrelated donors. Most patients (94·3%) were given anti-T-cell antibodies. The incidence of acute graft-versus-host disease (GVHD) of grades II-IV was 32·1% and that of chronic GVHD was 30·2%. The 3-year probability of non-relapse mortality (NRM) was 25·9%, that of relapse was 48·5%, that of GVHD-free and relapse-free survival (GRFS) was 17·8% and that of leukaemia-free survival (LFS) was 25·6%. In multivariate analysis, unrelated donor recipients more frequently had acute GVHD of grades II-IV [hazard ratio (HR) = 1·98, P = 0·017] and suffered less relapses (HR = 0·62, P = 0·01) than MSD recipients. Treatment with anti-T-cell antibodies reduced NRM (HR = 0·35, P = 0·01) and improved survival (HR = 0·49, P = 0·01), GRFS (HR = 0·37, P = 0·0004) and LFS (HR = 0·46, P = 0·005). Thus, sequential chemotherapy followed by RIC HSCT and use of anti-T-cell antibodies seems promising in patients with refractory AML. © 2016 John Wiley & Sons Ltd.

76 FR 59392 - Notice of Intent To Grant Exclusive Patent License; Enhanced Energy Group, LLC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-26

... inventions, and they are covered by U.S. Patent No. 7,926,275: Closed Brayton Cycle Direct Contact Reactor/ Storage Tank With Chemical Scrubber.//U.S. Patent No. 7,926,276: Closed Cycle Brayton Propulsion System With Direct Heat Transfer.//U.S. Patent No. 7,937,930: Semiclosed Brayton Cycle Power System With...

Fibrin(ogen) is internalized and degraded by activated human monocytoid cells via Mac-1 (CD11b/CD18): a nonplasmin fibrinolytic pathway.

PubMed

Simon, D I; Ezratty, A M; Francis, S A; Rennke, H; Loscalzo, J

1993-10-15

Fibrin(ogen) (FGN) is important for hemostasis and wound healing and is cleared from sites of injury primarily by the plasminogen activator system. However, there is emerging evidence in plasminogen activator-deficient transgenic mice that nonplasmin pathways may be important in fibrin(ogen)olysis, as well. Given the proximity of FGN and monocytes within the occlusive thrombus at sites of vascular injury, we considered the possibility that monocytes may play an ancillary role in the degradation and clearance of fibrin. We found that monocytes possess an alternative fibrinolytic pathway that uses the integrin Mac-1, which directly binds and internalizes FGN, resulting in its lysosomal degradation. At 4 degrees C, FGN binds to U937 monocytoid cells in a specific and saturable manner with a kd of 1.8 mumol/L. Binding requires adenosine diphosphate stimulation and is calcium-dependent. At 37 degrees C, FGN and fibrin monomer (FM) are internalized and degraded at rates of 0.37 +/- 0.13 and 0.55 +/- 0.03 microgram/10(6) cells/h by U937 cells, 1.38 +/- 0.02 and 1.20 +/- 0.30 microgram/10(6) cells/h by THP-1 cells, and 2.10 +/- 0.20 and 2.52 +/- 0.18 micrograms/10(6) cells/h by human peripheral blood mononuclear cells, respectively. The serine protease inhibitors, PPACK and aprotinin, and the specific elastase inhibitor, AAPVCK, do not significantly inhibit degradation. However, degradation is inhibited by chloroquine, suggesting that a lysosomal pathway is involved. Factor X, a competitive ligand with FGN for the Mac-1 receptor, also blocks degradation, as does a monoclonal antibody to the alpha-subunit of Mac-1. Autoradiography of radioiodinated, internalized FGN shows that FGN proteolysis by the pathway produces a unique degradation pattern distinct from that observed with plasmin. In a fibrin clot lysis assay, Mac-1-mediated fibrinolysis contributed significantly to total fibrinolysis. In summary, FGN is internalized and degraded by activated human monocytoid cells via Mac-1 in the absence of plasmin, thereby providing an alternative fibrinolytic pathway. Thus, in addition to the function of cell adhesion, integrins may also act as receptors that mediate the internalization and degradation of bound ligands.

Inflammatory and Oxidative Responses Induced by Exposure to Commonly Used e-Cigarette Flavoring Chemicals and Flavored e-Liquids without Nicotine.

PubMed

Muthumalage, Thivanka; Prinz, Melanie; Ansah, Kwadwo O; Gerloff, Janice; Sundar, Isaac K; Rahman, Irfan

2017-01-01

Background: The respiratory health effects of inhalation exposure to e-cigarette flavoring chemicals are not well understood. We focused our study on the immuno-toxicological and the oxidative stress effects by these e-cigarette flavoring chemicals on two types of human monocytic cell lines, Mono Mac 6 (MM6) and U937. The potential to cause oxidative stress by these flavoring chemicals was assessed by measuring the production of reactive oxygen species (ROS). We hypothesized that the flavoring chemicals used in e-juices/e-liquids induce an inflammatory response, cellular toxicity, and ROS production. Methods: Two monocytic cell types, MM6 and U937 were exposed to commonly used e-cigarette flavoring chemicals; diacetyl, cinnamaldehyde, acetoin, pentanedione, o-vanillin, maltol and coumarin at different doses between 10 and 1,000 μM. Cell viability and the concentrations of the secreted inflammatory cytokine interleukin 8 (IL-8) were measured in the conditioned media. Cell-free ROS produced by these commonly used flavoring chemicals were also measured using a 2',7'dichlorofluorescein diacetate probe. These DCF fluorescence data were expressed as hydrogen peroxide (H 2 O 2 ) equivalents. Cytotoxicity due to the exposure to selected e-liquids was assessed by cell viability and the IL-8 inflammatory cytokine response in the conditioned media. Results: Treatment of the cells with flavoring chemicals and flavored e-liquid without nicotine caused cytotoxicity dose-dependently. The exposed monocytic cells secreted interleukin 8 (IL-8) chemokine in a dose-dependent manner compared to the unexposed cell groups depicting a biologically significant inflammatory response. The measurement of cell-free ROS by the flavoring chemicals and e-liquids showed significantly increased levels of H 2 O 2 equivalents in a dose-dependent manner compared to the control reagents. Mixing a variety of flavors resulted in greater cytotoxicity and cell-free ROS levels compared to the treatments with individual flavors, suggesting that mixing of multiple flavors of e-liquids are more harmful to the users. Conclusions: Our data suggest that the flavorings used in e-juices can trigger an inflammatory response in monocytes, mediated by ROS production, providing insights into potential pulmonary toxicity and tissue damage in e-cigarette users.

Inflammatory and Oxidative Responses Induced by Exposure to Commonly Used e-Cigarette Flavoring Chemicals and Flavored e-Liquids without Nicotine

PubMed Central

Muthumalage, Thivanka; Prinz, Melanie; Ansah, Kwadwo O.; Gerloff, Janice; Sundar, Isaac K.; Rahman, Irfan

2018-01-01

Background: The respiratory health effects of inhalation exposure to e-cigarette flavoring chemicals are not well understood. We focused our study on the immuno-toxicological and the oxidative stress effects by these e-cigarette flavoring chemicals on two types of human monocytic cell lines, Mono Mac 6 (MM6) and U937. The potential to cause oxidative stress by these flavoring chemicals was assessed by measuring the production of reactive oxygen species (ROS). We hypothesized that the flavoring chemicals used in e-juices/e-liquids induce an inflammatory response, cellular toxicity, and ROS production. Methods: Two monocytic cell types, MM6 and U937 were exposed to commonly used e-cigarette flavoring chemicals; diacetyl, cinnamaldehyde, acetoin, pentanedione, o-vanillin, maltol and coumarin at different doses between 10 and 1,000 μM. Cell viability and the concentrations of the secreted inflammatory cytokine interleukin 8 (IL-8) were measured in the conditioned media. Cell-free ROS produced by these commonly used flavoring chemicals were also measured using a 2′,7′dichlorofluorescein diacetate probe. These DCF fluorescence data were expressed as hydrogen peroxide (H2O2) equivalents. Cytotoxicity due to the exposure to selected e-liquids was assessed by cell viability and the IL-8 inflammatory cytokine response in the conditioned media. Results: Treatment of the cells with flavoring chemicals and flavored e-liquid without nicotine caused cytotoxicity dose-dependently. The exposed monocytic cells secreted interleukin 8 (IL-8) chemokine in a dose-dependent manner compared to the unexposed cell groups depicting a biologically significant inflammatory response. The measurement of cell-free ROS by the flavoring chemicals and e-liquids showed significantly increased levels of H2O2 equivalents in a dose-dependent manner compared to the control reagents. Mixing a variety of flavors resulted in greater cytotoxicity and cell-free ROS levels compared to the treatments with individual flavors, suggesting that mixing of multiple flavors of e-liquids are more harmful to the users. Conclusions: Our data suggest that the flavorings used in e-juices can trigger an inflammatory response in monocytes, mediated by ROS production, providing insights into potential pulmonary toxicity and tissue damage in e-cigarette users. PMID:29375399

Interaction of β(3) /β(2) -peptides, consisting of Val-Ala-Leu segments, with POPC giant unilamellar vesicles (GUVs) and white blood cancer cells (U937)--a new type of cell-penetrating peptides, and a surprising chain-length dependence of their vesicle- and cell-lysing activity.

PubMed

Kolesinska, Beata; Eyer, Klaus; Robinson, Tom; Dittrich, Petra S; Beck, Albert K; Seebach, Dieter; Walde, Peter

2015-05-01

Many years ago, β(2) /β(3) -peptides, consisting of alternatively arranged β(2) - and β(3) h-amino-acid residues, have been found to undergo folding to a unique type of helix, the 10/12-helix, and to exhibit non-polar, lipophilic properties (Helv. Chim. Acta 1997, 80, 2033). We have now synthesized such 'mixed' hexa-, nona-, dodeca-, and octadecapeptides, consisting of Val-Ala-Leu triads, with N-terminal fluorescein (FAM) labels, i.e., 1-4, and studied their interactions with POPC (=1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) giant unilamellar vesicles (GUVs) and with human white blood cancer cells U937. The methods used were microfluidic technology, fluorescence correlation spectroscopy (FCS), a flow-cytometry assay, a membrane-toxicity assay with the dehydrogenase G6PDH as enzymatic reporter, and visual microscopy observations. All β(3) /β(2) -peptide derivatives penetrate the GUVs and/or the cells. As shown with the isomeric β(3) /β(2) -, β(3) -, and β(2) -nonamers, 2, 5, and 6, respectively, the derivatives 5 and 6 consisting exclusively of β(3) - or β(2) -amino-acid residues, respectively, interact neither with the vesicles nor with the cells. Depending on the method of investigation and on the pretreatment of the cells, the β(3) /β(2) -nonamer and/or the β(3) /β(2) -dodecamer derivative, 2 and/or 3, respectively, cause a surprising disintegration or lysis of the GUVs and cells, comparable with the action of tensides, viral fusion peptides, and host-defense antimicrobial peptides. Possible sources of the chain-length-dependent destructive potential of the β(3) /β(2) -nona- and β(3) /β(2) -dodecapeptide derivatives, and a possible relationship with the phosphate-to-phosphate and hydrocarbon thicknesses of GUVs, and eukaryotic cells are discussed. Further investigations with other types of GUVs and of eukaryotic or prokaryotic cells will be necessary to elucidate the mechanism(s) of interaction of 'mixed' β(3) /β(2) -peptides with membranes and to evaluate possible biomedical applications. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

Anti-LRP/LR Specific Antibody IgG1-iS18 Impedes Adhesion and Invasion of Liver Cancer Cells

PubMed Central

Chetty, Carryn; Khumalo, Thandokuhle; Da Costa Dias, Bianca; Reusch, Uwe; Knackmuss, Stefan; Little, Melvyn; Weiss, Stefan F. T.

2014-01-01

Two key events, namely adhesion and invasion, are pivotal to the occurrence of metastasis. Importantly, the 37 kDa/67 kDa laminin receptor (LRP/LR) has been implicated in enhancing these two events thus facilitating cancer progression. In the current study, the role of LRP/LR in the adhesion and invasion of liver cancer (HUH-7) and leukaemia (K562) cells was investigated. Flow cytometry revealed that the HUH-7 cells displayed significantly higher cell surface LRP/LR levels compared to the poorly-invasive breast cancer (MCF-7) control cells, whilst the K562 cells displayed significantly lower cell surface LRP/LR levels in comparison to the MCF-7 control cells. However, Western blotting and densitometric analysis revealed that all three tumorigenic cell lines did not differ significantly with regards to total LRP/LR levels. Furthermore, treatment of liver cancer cells with anti-LRP/LR specific antibody IgG1-iS18 (0.2 mg/ml) significantly reduced the adhesive potential of cells to laminin-1 and the invasive potential of cells through the ECM-like Matrigel, whilst leukaemia cells showed no significant differences in both instances. Additionally, Pearson's correlation coefficients suggested direct proportionality between cell surface LRP/LR levels and the adhesive and invasive potential of liver cancer and leukaemia cells. These findings suggest the potential use of anti-LRP/LR specific antibody IgG1-iS18 as an alternative therapeutic tool for metastatic liver cancer through impediment of the LRP/LR- laminin-1 interaction. PMID:24798101

Use of an adaptable cell culture kit for performing lymphocyte and monocyte cell cultures in microgravity

NASA Technical Reports Server (NTRS)

Hatton, J. P.; Lewis, M. L.; Roquefeuil, S. B.; Chaput, D.; Cazenave, J. P.; Schmitt, D. A.

1998-01-01

The results of experiments performed in recent years on board facilities such as the Space Shuttle/Spacelab have demonstrated that many cell systems, ranging from simple bacteria to mammalian cells, are sensitive to the microgravity environment, suggesting gravity affects fundamental cellular processes. However, performing well-controlled experiments aboard spacecraft offers unique challenges to the cell biologist. Although systems such as the European 'Biorack' provide generic experiment facilities including an incubator, on-board 1-g reference centrifuge, and contained area for manipulations, the experimenter must still establish a system for performing cell culture experiments that is compatible with the constraints of spaceflight. Two different cell culture kits developed by the French Space Agency, CNES, were recently used to perform a series of experiments during four flights of the 'Biorack' facility aboard the Space Shuttle. The first unit, Generic Cell Activation Kit 1 (GCAK-1), contains six separate culture units per cassette, each consisting of a culture chamber, activator chamber, filtration system (permitting separation of cells from supernatant in-flight), injection port, and supernatant collection chamber. The second unit (GCAK-2) also contains six separate culture units, including a culture, activator, and fixation chambers. Both hardware units permit relatively complex cell culture manipulations without extensive use of spacecraft resources (crew time, volume, mass, power), or the need for excessive safety measures. Possible operations include stimulation of cultures with activators, separation of cells from supernatant, fixation/lysis, manipulation of radiolabelled reagents, and medium exchange. Investigations performed aboard the Space Shuttle in six different experiments used Jurkat, purified T-cells or U937 cells, the results of which are reported separately. We report here the behaviour of Jurkat and U937 cells in the GCAK hardware in ground-based investigations simulating the conditions expected in the flight experiment. Several parameters including cell concentration, time between cell loading and activation, and storage temperature on cell survival were examined to characterise cell response and optimise the experiments to be flown aboard the Space Shuttle. Results indicate that the objectives of the experiments could be met with delays up to 5 days between cell loading into the hardware and initial in flight experiment activation, without the need for medium exchange. Experiment hardware of this kind, which is adaptable to a wide range of cell types and can be easily interfaced to different spacecraft facilities, offers the possibility for a wide range of experimenters successfully and easily to utilise future flight opportunities.

Plant extracts of spices and coffee synergistically dampen nuclear factor-κB in U937 cells.

PubMed

Kolberg, Marit; Paur, Ingvild; Balstad, Trude R; Pedersen, Sigrid; Jacobs, David R; Blomhoff, Rune

2013-10-01

A large array of bioactive plant compounds (phytochemicals) has been identified and synergy among these compounds might contribute to the beneficial effects of plant foods. The transcription factor nuclear factor-κB (NF-κB) has been suggested as a target for many phytochemicals. Due to the complexity of mechanisms involved in NF-κB regulation, including numerous feedback loops, and the large number of phytochemicals which regulate NF-κB activity, we hypothesize that synergistic or antagonistic effects are involved. The objectives of our study were to develop a statistical methodology to evaluate the concept of synergy and antagonism and to use this methodology in a monocytic cell line (U937 expressing an NF-κB-luciferase reporter) treated with lipopolysaccharide and phytochemical-rich plant extracts. Both synergistic and antagonistic effects were clearly observed. Observed synergy was most pronounced for the combinations of oregano and coffee, and thyme and oregano. For oregano and coffee the synergistic effect was highest at 5 mg/mL with 13.9% (P < .001), and for thyme and oregano the highest synergistic effects was at 3 mg/mL with 13.7% (P < .001). Dose dependent synergistic and antagonistic effects were observed for all combinations tested. In conclusion, this work presents a methodological tool to define synergy in experimental studies. Our results support the hypothesis that phytochemical-rich plants may exert synergistic and antagonistic effects on NF-κB regulation. Such complex mechanistic interactions between phytochemicals are likely to underlie the protective effects of a plant-based diet on life-style related diseases. © 2013 Elsevier Inc. All rights reserved.

Hepatic fat accumulation and regulation of FAT/CD36: an effect of hepatic irradiation

PubMed Central

Martius, Gesa; Alwahsh, Salamah Mohammad; Rave-Fränk, Margret; Hess, Clemens Friedrich; Christiansen, Hans; Ramadori, Giuliano; Malik, Ihtzaz Ahmed

2014-01-01

Irradiation is known to induce inflammation and affect fat metabolic pathways. The current study investigates hepatic fat accumulation and fatty acid transportation in a rat model of single dose liver irradiation (25-Gy). Rat livers were selectively irradiated in-vivo (25-Gy), sham-irradiated rats served as controls. Hepatic lipids were studied by colorimetric assays in liver and serum. Intracellular lipids, protein and mRNA were studied by Nile red staining, immunohistology, Western Blot analysis and RT-PCR in liver, respectively. Changes in FAT/CD36 expression were studied in-vitro in a human monocyte cell line U937 after irradiation in presence or absence of infliximab (IFX). Nile Red staining of liver cryosections showed a quick (12-48 h) increase in fat droplets. Accordingly, hepatic triglycerides (TG) and free fatty acids (FFA) were elevated. An early increase (3-6 h) in the serum level of HDL-C, TG and cholesterol was measured after single dose irradiation followed by a decrease thereafter. Furthermore, expression of the fat transporter protein FAT/CD36 was increased, immunohistochemistry revealed basolateral and cytoplasmic expression in hepatocytes. Moreover, apolipoprotein-B100, -C3 and enzymes (acetyl-CoA carboxylase, lipoprotein-lipase, carnitine-palmitoyltransferase, malonyl-CoA-decarboxylase) involved in fat metabolism were induced at 12-24 h. Early activation of the NFkβ pathway (IκBα) by TNF-α was seen, followed by a significant elevation of serum markers for liver damage (AST and GLDH). TNF-α blockage by anti-TNF-α in cell culture (U937) prevented the increase of FAT/CD36 caused by irradiation. Selective liver irradiation is a model for rapid induction of steatosis hepatis and fat accumulation could be triggered by irradiation-induced inflammatory mediators (e.g. TNF-α). PMID:25197426

Amine-Rich Organic Thin Films for Cell Culture: Possible Electrostatic Effects in Cell-Surface Interactions

NASA Astrophysics Data System (ADS)

Wertheimer, Michael R.; St-Georges-Robillard, Amélie; Lerouge, Sophie; Mwale, Fackson; Elkin, Bentsian; Oehr, Christian; Wirges, Werner; Gerhard, Reimund

2012-11-01

In recent communications from these laboratories, we observed that amine-rich thin organic layers are very efficient surfaces for the adhesion of mammalian cells. We prepare such deposits by plasma polymerization at low pressure, atmospheric pressure, or by vacuum-ultraviolet photo-polymerization. More recently, we have also investigated a commercially available material, Parylene diX AM. In this article we first briefly introduce literature relating to electrostatic interactions between cells, proteins, and charged surfaces. We then present certain selected cell-response results that pertain to applications in orthopedic and cardiovascular medicine: we discuss the influence of surface properties on the observed behaviors of two particular cell lines, human U937 monocytes, and Chinese hamster ovary cells. Particular emphasis is placed on possible electrostatic attractive forces due to positively charged R-NH3+ groups and negatively charged proteins and cells, respectively. Experiments carried out with electrets, polymers with high positive or negative surface potentials are added for comparison.

Clinical outcomes of a novel therapeutic vaccine with Tax peptide-pulsed dendritic cells for adult T cell leukaemia/lymphoma in a pilot study.

PubMed

Suehiro, Youko; Hasegawa, Atsuhiko; Iino, Tadafumi; Sasada, Amane; Watanabe, Nobukazu; Matsuoka, Masao; Takamori, Ayako; Tanosaki, Ryuji; Utsunomiya, Atae; Choi, Ilseung; Fukuda, Tetsuya; Miura, Osamu; Takaishi, Shigeo; Teshima, Takanori; Akashi, Koichi; Kannagi, Mari; Uike, Naokuni; Okamura, Jun

2015-05-01

Adult T cell leukaemia/lymphoma (ATL) is a human T cell leukaemia virus type-I (HTLV-I)-infected T cell malignancy with poor prognosis. We herein developed a novel therapeutic vaccine designed to augment an HTLV-I Tax-specific cytotoxic T lymphocyte (CTL) response that has been implicated in anti-ATL effects, and conducted a pilot study to investigate its safety and efficacy. Three previously treated ATL patients, classified as intermediate- to high-risk, were subcutaneously administered with the vaccine, consisting of autologous dendritic cells (DCs) pulsed with Tax peptides corresponding to the CTL epitopes. In all patients, the performance status improved after vaccination without severe adverse events, and Tax-specific CTL responses were observed with peaks at 16-20 weeks. Two patients achieved partial remission in the first 8 weeks, one of whom later achieved complete remission, maintaining their remission status without any additional chemotherapy 24 and 19 months after vaccination, respectively. The third patient, whose tumour cells lacked the ability to express Tax at biopsy, obtained stable disease in the first 8 weeks and later developed slowly progressive disease although additional therapy was not required for 14 months. The clinical outcomes of this pilot study indicate that the Tax peptide-pulsed DC vaccine is a safe and promising immunotherapy for ATL. © 2015 John Wiley & Sons Ltd.

[Advances in the treatment of chronic lymphocytic leukaemia].

PubMed

Mozas, Pablo; Delgado, Julio

2016-11-18

Chronic lymphocytic leukemia (CLL), a proliferation of mature B cells, is one of the most prevalent haematological malignancies. Progress has been made in its treatment during the last few decades, and chemoimmunotherapy based on fludarabine, cyclophosphamide and rituximab is considered the treatment of choice for patients with standard-risk CLL and good performance status. However, due to the characterization of high-risk biological subgroups and its presentation in elderly patients and/or with comorbidities, targeted therapies, such as B-cell receptor inhibitors, have been developed and approved during the last few years. The current review examines traditional therapeutic strategies and focuses on new small molecules that already represent promising elements of the CLL treatment landscape. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

Electron microscopy localization and characterization of functionalized composite organic-inorganic SERS nanoparticles on leukemia cells.

PubMed

Koh, Ai Leen; Shachaf, Catherine M; Elchuri, Sailaja; Nolan, Garry P; Sinclair, Robert

2008-12-01

We demonstrate the use of electron microscopy as a powerful characterization tool to identify and locate antibody-conjugated composite organic-inorganic nanoparticle (COINs) surface enhanced Raman scattering (SERS) nanoparticles on cells. U937 leukemia cells labeled with antibody CD54-conjugated COINs were characterized in their native, hydrated state using wet scanning electron microscopy (SEM) and in their dehydrated state using high-resolution SEM. In both cases, the backscattered electron (BSE) detector was used to detect and identify the silver constituents in COINs due to its high sensitivity to atomic number variations within a specimen. The imaging and analytical capabilities in the SEM were further complemented by higher resolution transmission electron microscopy (TEM) images and scanning Auger electron spectroscopy (AES) data to give reliable and high-resolution information about nanoparticles and their binding to cell surface antigens.

Electron Microscopy Localization and Characterization of Functionalized Composite Organic-Inorganic SERS Nanoparticles on Leukemia Cells

PubMed Central

Koh, Ai Leen; Shachaf, Catherine M.; Elchuri, Sailaja; Nolan, Garry P.; Sinclair, Robert

2008-01-01

We demonstrate the use of electron microscopy as a powerful characterization tool to identify and locate antibody-conjugated composite organic-inorganic (COINs) surface enhanced Raman scattering (SERS) nanoparticles on cells. U937 leukemia cells labeled with antibody CD54-conjugated COINs were characterized in their native, hydrated state using wet Scanning Electron Microscopy (SEM) and in their dehydrated state using high-resolution SEM. In both cases, the backscattered electron detector (BSE) was used to detect and identify the silver constituents in COINs due to its high sensitivity to atomic number variations within a specimen. The imaging and analytical capabilities in the SEM were further complemented by higher resolution Transmission Electron Microscope (TEM) images and Scanning Auger Electron Spectroscopy (AES) data to give reliable and high-resolution information about nanoparticles and their binding to cell surface antigens. PMID:18995965

Bone marrow trephine morphology and immunohistochemical findings in chronic myelomonocytic leukaemia.

PubMed

Ngo, Nye-Thane; Lampert, Irvin A; Naresh, Kikkeri N

2008-06-01

Chronic myelomonocytic leukaemia (CMML) is a clonal disorder with myelodysplastic/myeloproliferative features. Its diagnosis is based on the presence of peripheral blood monocytosis and bone marrow aspirate findings, according to World Health Organization criteria. However, bone marrow trephine biopsy (BMTB) features characteristic of CMML have not been adequately investigated. We studied BMTB in 20 cases of CMML-1 and three cases of CMML-2 and compared with ten cases of polycythaemia vera, ten cases of chronic myeloid leukaemia (chronic phase) and ten cases of florid myeloid hyperplasia (MH). Furthermore, we evaluated the use of CD34, CD117 and CD68 (PGM-1) antibodies in diagnosis and subtyping of CMML and in differentiating from other categories. Hypercellularity, high myeloid:erythroid ratio, increased proportion of 'myelo/monocytic' cells often seen as clusters and/or nodules, absence of eosinophilia, and presence of abnormal localisation of immature precursors (ALIP) and dysmegakaryopoiesis can aid in the diagnosis of CMML in BMTB. CD68 (PGM-1) positive cells amounted to 20.7 +/- 6.1% cells among CMML trephines. The proportion of CD34(+) cells among cases of CMML-1 was /=10% cells in two of three cases and 5% in the other case. Morphological and immunohistochemical features of BMTB samples are extremely helpful in the diagnosis of CMML.

Properly Substituted Analogues of BIX-01294 Lose Inhibition of G9a Histone Methyltransferase and Gain Selective Anti-DNA Methyltransferase 3A Activity

PubMed Central

Rotili, Dante; Tarantino, Domenico; Marrocco, Biagina; Gros, Christina; Masson, Véronique; Poughon, Valérie; Ausseil, Fréderic; Chang, Yanqi; Labella, Donatella; Cosconati, Sandro; Di Maro, Salvatore; Novellino, Ettore; Schnekenburger, Michael; Grandjenette, Cindy; Bouvy, Celine; Diederich, Marc; Cheng, Xiaodong; Arimondo, Paola B.; Mai, Antonello

2014-01-01

Chemical manipulations performed on the histone H3 lysine 9 methyltransferases (G9a/GLP) inhibitor BIX-01294 afforded novel desmethoxyquinazolines able to inhibit the DNA methyltransferase DNMT3A at low micromolar levels without any significant inhibition of DNMT1 and G9a. In KG-1 cells such compounds, when tested at sub-toxic doses, induced the luciferase re-expression in a stable construct controlled by a cytomegalovirus (CMV) promoter silenced by methylation (CMV-luc assay). Finally, in human lymphoma U-937 and RAJI cells, the N-(1-benzylpiperidin-4-yl)-2-(4-phenylpiperazin-1-yl)quinazolin-4-amine induced the highest proliferation arrest and cell death induction starting from 10 µM, in agreement with its DNMT3A inhibitory potency. PMID:24810902

Sinonasal Lymphoma Presenting as a Probable Sanctuary Site for Relapsed B Acute Lymphoblastic Leukaemia: A Case Report and Review of the Literature.

PubMed

Lim, W Y; Care, R; Lau, M; Chiruka, S; Dawes, P J D

2015-01-01

Sinonasal lymphoma is a non-Hodgkin lymphoma (NHL) representing 1.5% of all lymphomas. It presents as an unremitting ulceration with progressive destruction of midline sinonasal and surrounding structures. Poor prognosis warrants early treatment although diagnosis is challenging and frequently delayed. It is usually primary in origin and to our knowledge the sinonasal region has never been reported as a sanctuary site in leukaemia/lymphoma relapse. We present a unique case of B-cell ALL (acute lymphoblastic leukaemia) with late relapse to the nasal septum as a sinonasal lymphoblastic lymphoma and with genetic support for this as a sanctuary site.

Mechanistic mathematical modelling of mercaptopurine effects on cell cycle of human acute lymphoblastic leukaemia cells

PubMed Central

Panetta, J C; Evans, W E; Cheok, M H

2006-01-01

The antimetabolite mercaptopurine (MP) is widely used to treat childhood acute lymphoblastic leukaemia (ALL). To study the dynamics of MP on the cell cycle, we incubated human T-cell leukaemia cell lines (Molt-4 sensitive and resistant subline and P12 resistant) with 10 μM MP and measured total cell count, cell cycle distribution, percent viable, percent apoptotic, and percent dead cells serially over 72 h. We developed a mathematical model of the cell cycle dynamics after treatment with MP and used it to show that the Molt-4 sensitive controls had a significantly higher rate of cells entering apoptosis (2.7-fold, P<0.00001) relative to the resistant cell lines. Additionally, when treated with MP, the sensitive cell line showed a significant increase in the rate at which cells enter apoptosis compared to its controls (2.4-fold, P<0.00001). Of note, the resistant cell lines had a higher rate of antimetabolite incorporation into the DNA of viable cells (>1.4-fold, P<0.01). Lastly, in contrast to the other cell lines, the Molt-4 resistant subline continued to cycle, though at a rate slower relative to its control, rather than proceed to apoptosis. This led to a larger S-phase block in the Molt-4 resistant cell line, but not a higher rate of cell death. Gene expression of apoptosis, cell cycle, and repair genes were consistent with mechanistic dynamics described by the model. In summary, the mathematical model provides a quantitative assessment to compare the cell cycle effects of MP in cells with varying degrees of MP resistance. PMID:16333308

Genomic characterization of Imatinib resistance in CD34+ cell populations from chronic myeloid leukaemia patients.

PubMed

Joha, Sami; Dauphin, Véronique; Leprêtre, Frédéric; Corm, Sélim; Nicolini, Franck E; Roumier, Christophe; Nibourel, Olivier; Grardel, Nathalie; Maguer-Satta, Véronique; Idziorek, Thierry; Figeac, Martin; Laï, Jean-Luc; Quesnel, Bruno; Etienne, Gabriel; Guilhot, François; Lippert, Eric; Preudhomme, Claude; Roche-Lestienne, Catherine

2011-04-01

To ascertain genomic alterations associated with Imatinib resistance in chronic myeloid leukaemia, we performed high resolution genomic analysis of CD34(+) cells from 25 Imatinib (IM) resistant and 11 responders CML patients. Using patients' T-cells as reference, we found significant association between number of acquired cryptic copy number alterations (CNA) and disease phase (p=0.036) or loss of IM response for patients diagnosed in chronic phase (CP) (p=0.04). Recurrent cryptic losses were identified on chromosomes 7, 12 and 13. On chromosome 7, recurrent deletions of the IKZF1 locus were detected, for the first time, in 4 patients in CP. Copyright © 2010 Elsevier Ltd. All rights reserved.

Hairy cell leukaemia complicated by anti-MAG paraproteinemic demyelinating neuropathy: resolution of neurological syndrome after cladribrine treatment.

PubMed

Rossi, Davide; Franceschetti, Silvia; Cerri, Michaela; Conconi, Annarita; Lunghi, Monia; Capello, Daniela; Cantello, Roberto; Gaidano, Gianluca

2007-06-01

Hairy cell leukaemia (HCL) occasionally displays a monoclonal gammopathy, yet the association of HCL with paraproteinemic demyelinating neuropathy (PDN) has not been reported. We describe a HCL case complicated by PDN and high titers of monoclonal IgM against myelin associated glycoprotein (MAG). Heavy and light chains of the patient's anti-MAG monoclonal protein were consistent with those expressed by HCL cells. After treatment with cladribrine, remission of HCL strictly paralleled disappearance of the IgM monoclonal protein and of the serum anti-MAG activity, and led to PDN clinical and electrophysiological improvement. Purine analogs may represent a choice in IgM PDN associated with lymphoproliferative disorders.

Unusual Methylobacterium fujisawaense Infection in a Patient with Acute Leukaemia Undergoing Hematopoietic Stem Cell Transplantation: First Case Report

PubMed Central

Fanci, Rosa; Corti, Giampaolo; Bartoloni, Alessandro; Tortoli, Enrico; Mariottini, Alessandro; Pecile, Patrizia

2010-01-01

Microorganisms of the genus Methylobacterium are facultative methylotrophic, gram-negative rods that are ubiquitous in nature and rarely cause human disease, mostly in subjects with preexisting causes of immune depression. Methylobacterium fujisawaense, first proposed as a new species in 1988, has never been reported as a bacterial agent of human infections so far. Here we describe a case of M. fujisawaense infection in a relapsed acute leukaemia undergoing unrelated allogeneic hematopoietic stem cell transplantation. Molecular identification of an M. fujisawaense strain was obtained from multiple mycobacterial blood cultures. PMID:20396386

Interferon in chronic myeloid leukaemia: past and future.

PubMed

Guilhot, François; Roy, Lydia; Saulnier, Pierre-Jean; Guilhot, Joëlle

2009-09-01

Imatinib has revolutionized the therapy of chronic myeloid leukaemia. However the complete eradication of leukaemic stem cells is still a matter of discussion. Interferon (IFN) has been used in the past with success. However the proportion of patients who achieved sustained complete cytogenetic response was small. Recently, in addition to its direct antineoplastic effect and immunomodulatory activity, IFN has been shown to stimulate the quiescent leukaemic stem cells. Thus there is now a rational for combining Imatinib and IFN. Large prospective phase III trials are in good progress to demonstrate in humans the usefullness of a combination therapy using Imatinib and IFN.

The distribution of MLL breakpoints correlates with outcome in infant acute leukaemia.

PubMed

Emerenciano, Mariana; Meyer, Claus; Mansur, Marcela B; Marschalek, Rolf; Pombo-de-Oliveira, Maria S

2013-04-01

Acute leukaemia in early childhood - and mainly infant leukaemia (IL) - is characterized by acquired genetic alterations, most commonly by the presence of distinct MLL rearrangements (MLL-r). The aim of this study was to investigate possible correlations between clinical features and molecular analyses of a series of 545 childhood leukaemia (≤24 months of age) cases: 385 acute lymphoblastic leukaemia (ALL) and 160 acute myeloid leukaemia (AML). The location of the genomic breakpoints was determined in a subset of 30 MLL-r cases. The overall survival of the investigated cohort was 60·5%, as determined by the Kaplan-Meier method. Worse outcomes were associated with age at diagnosis ≤6 months (P < 0·001), high white blood cell count (P = 0·001), and MLL-r (P = 0·002) in ALL, while children with AML displayed a poorer outcome (P = 0·009) regardless of their age strata. Moreover, we present first evidence that MLL-r patients with poor outcome preferentially displayed chromosomal breakpoints within MLL intron 11. Based on the literature, most MLL-r IL display a breakpoint localization towards intron 11, which in turn may explain their worse clinical course. In summary, the MLL breakpoint localization is of clinical importance and should be considered as a novel outcome predictor for MLL-r patients. © 2013 Blackwell Publishing Ltd.

Genomic Imbalances Are Confined to Non-Proliferating Cells in Paediatric Patients with Acute Myeloid Leukaemia and a Normal or Incomplete Karyotype

PubMed Central

Ballabio, Erica; Regan, Regina; Garimberti, Elisa; Harbott, Jochen; Bradtke, Jutta; Teigler-Schlegel, Andrea; Biondi, Andrea; Cazzaniga, Giovanni; Giudici, Giovanni; Wainscoat, James S.; Boultwood, Jacqueline; Bridger, Joanna M.; Knight, Samantha J. L.; Tosi, Sabrina

2011-01-01

Leukaemia is often associated with genetic alterations such as translocations, amplifications and deletions, and recurrent chromosome abnormalities are used as markers of diagnostic and prognostic relevance. However, a proportion of acute myeloid leukaemia (AML) cases have an apparently normal karyotype despite comprehensive cytogenetic analysis. Based on conventional cytogenetic analysis of banded chromosomes, we selected a series of 23 paediatric patients with acute myeloid leukaemia and performed whole genome array comparative genome hybridization (aCGH) using DNA samples derived from the same patients. Imbalances involving large chromosomal regions or entire chromosomes were detected by aCGH in seven of the patients studied. Results were validated by fluorescence in situ hybridization (FISH) to both interphase nuclei and metaphase chromosomes using appropriate bacterial artificial chromosome (BAC) probes. The majority of these copy number alterations (CNAs) were confirmed by FISH and found to localize to the interphase rather than metaphase nuclei. Furthermore, the proliferative states of the cells analyzed by FISH were tested by immunofluorescence using an antibody against the proliferation marker pKi67. Interestingly, these experiments showed that, in the vast majority of cases, the changes appeared to be confined to interphase nuclei in a non-proliferative status. PMID:21694761

[Neurological complications in the population of children with leukaemia].

PubMed

Martínez-Cayuelas, Elena; Domingo-Jiménez, Rosario; Pascual-Gázquez, Juan F; Martínez-Salcedo, Eduardo; Alarcón-Martínez, Helena; Bermúdez-Cortés, Mar; Fuster-Soler, José L; Pérez-Fernández, Virginia

2015-02-01

Leukaemia is the most frequent type of cancer at the paediatric age. The cure rate is 80% with intensive chemotherapy, which improves survival but also often increases the frequency of adverse side effects, including those of a neurological nature. To describe the frequency and characteristics of the neurological complications (NC) in patients with acute lymphoid leukaemia (ALL) and acute myeloid leukaemia (AML), as well as to identify factors associated to their presence, neurological morbidity and survival rate. A retrospective study was conducted of the NC present in patients with ALL and AML between 1997 and 2012 treated and followed up by the child onco-haematology unit. The following variables were analysed: demographic data, oncological diagnosis, treatment and NC. Altogether 157 patients were included, 145 without infiltration of the central nervous system at diagnosis and eight with infiltration (rate of NC of 14% and 12%, respectively). The most frequent NC were: neuropathies (31%), altered levels of consciousness (27%), convulsions (22%) and headache (12%). Forty per cent of the patients with NC presented sequelae but none of them died as a consequence of the NC. More NC were detected in the age group of children aged under 6 years with high-degree ALL, at higher levels of severity and in patients who had received a haematopoietic stem-cell transplant, all of them with statistically significant differences. Neurological complications are common in patients with acute leukaemia, especially in those at a high-risk stage (above all if they are under the age of 6 years) and with haematopoietic stem-cell transplant. The associated mortality rate is low.

Lipopolysaccharide is a potent monocyte/macrophage-specific stimulator of human immunodeficiency virus type 1 expression

PubMed Central

1990-01-01

Lipopolysaccharide (LPS) potently stimulates human immunodeficiency virus type 1-long terminal repeat (HIV-1-LTR) CAT constructs transfected into monocyte/macrophage-like cell lines but not a T cell line. This effect appears to be mediated through the induction of nuclear factor kappa B (NF-kappa B). Electrophoretic mobility shift assays demonstrate that LPS induces a DNA binding activity indistinguishable from NF-kappa B in U937 and THP-1 cells. LPS is also shown to dramatically increase HIV-1 production from a chronically infected monocyte/macrophage-like cloned cell line, U1, which produces very low levels of HIV-1 at baseline. The stimulation of viral production from this cell line occurs only if these cells are treated with granulocyte/macrophage colony-stimulating factor (GM-CSF) before treatment with LPS. This stimulation of HIV-1 production is correlated with an increase in the level of HIV-1 RNA and and activation of NF- kappa B. LPS is not able to induce HIV-1 production in a cloned T cell line. The effect of LPS on HIV-1 replication occurs at picogram per milliliter concentrations and may be clinically significant in understanding the variability of the natural history of HIV-1 infection. PMID:2193097

Transcription control by the ENL YEATS domain in acute leukaemia.

PubMed

Erb, Michael A; Scott, Thomas G; Li, Bin E; Xie, Huafeng; Paulk, Joshiawa; Seo, Hyuk-Soo; Souza, Amanda; Roberts, Justin M; Dastjerdi, Shiva; Buckley, Dennis L; Sanjana, Neville E; Shalem, Ophir; Nabet, Behnam; Zeid, Rhamy; Offei-Addo, Nana K; Dhe-Paganon, Sirano; Zhang, Feng; Orkin, Stuart H; Winter, Georg E; Bradner, James E

2017-03-09

Recurrent chromosomal translocations producing a chimaeric MLL oncogene give rise to a highly aggressive acute leukaemia associated with poor clinical outcome. The preferential involvement of chromatin-associated factors as MLL fusion partners belies a dependency on transcription control. Despite recent progress made in targeting chromatin regulators in cancer, available therapies for this well-characterized disease remain inadequate, prompting the need to identify new targets for therapeutic intervention. Here, using unbiased CRISPR-Cas9 technology to perform a genome-scale loss-of-function screen in an MLL-AF4-positive acute leukaemia cell line, we identify ENL as an unrecognized gene that is specifically required for proliferation in vitro and in vivo. To explain the mechanistic role of ENL in leukaemia pathogenesis and dynamic transcription control, a chemical genetic strategy was developed to achieve targeted protein degradation. Acute loss of ENL suppressed the initiation and elongation of RNA polymerase II at active genes genome-wide, with pronounced effects at genes featuring a disproportionate ENL load. Notably, an intact YEATS chromatin-reader domain was essential for ENL-dependent leukaemic growth. Overall, these findings identify a dependency factor in acute leukaemia and suggest a mechanistic rationale for disrupting the YEATS domain in disease.

Perspectives of gene expression profiling for diagnosis and therapy in haematological malignancies.

PubMed

Bacher, Ulrike; Kohlmann, Alexander; Haferlach, Torsten

2009-05-01

Considering the heterogeneity of leukaemias and the widening spectrum of therapeutic strategies, novel diagnostic methods are urgently needed for haematological malignancies. For a decade, gene expression profiling (GEP) has been applied in leukaemia research. Thus, various studies demonstrated worldwide that the majority of genetically defined leukaemia subtypes are accurately predictable by GEP, for example, with respect to reciprocal rearrangements in acute myeloid leukaemia (AML). Moreover, novel prognostically relevant gene classifiers were developed as, for example, in normal karyotype AML. Considering the lymphatic malignancies, GEP studies defined novel clinically relevant subtypes in diffuse large B cell lymphoma (DLBCL), and improved the discrimination of Burkitt lymphoma and DLBCL cases, overcoming considerable overlaps of these entities that exist from morphological and genetic perspectives. Treatment-specific sensitivity assays are being developed for targeted drugs such as farnesyl transferase inhibitors in AML or imatinib in BCR-ABL1 positive acute lymphoblastic leukaemia (ALL). Irrespectively of these proceedings, an introduction of the microarray technology in haematological practice requires diagnostic algorithms and strategies for interaction with currently established diagnostic techniques. Large multicentre studies such as the MILE Study (Microarray Innovations in LEukemia) aim at translating this methodology into clinical routine workflows and to catalyze this process.

Childhood leukaemia risks: from unexplained findings near nuclear installations to recommendations for future research.

PubMed

Laurier, D; Grosche, B; Auvinen, A; Clavel, J; Cobaleda, C; Dehos, A; Hornhardt, S; Jacob, S; Kaatsch, P; Kosti, O; Kuehni, C; Lightfoot, T; Spycher, B; Van Nieuwenhuyse, A; Wakeford, R; Ziegelberger, G

2014-09-01

Recent findings related to childhood leukaemia incidence near nuclear installations have raised questions which can be answered neither by current knowledge on radiation risk nor by other established risk factors. In 2012, a workshop was organised on this topic with two objectives: (a) review of results and discussion of methodological limitations of studies near nuclear installations; (b) identification of directions for future research into the causes and pathogenesis of childhood leukaemia. The workshop gathered 42 participants from different disciplines, extending widely outside of the radiation protection field. Regarding the proximity of nuclear installations, the need for continuous surveillance of childhood leukaemia incidence was highlighted, including a better characterisation of the local population. The creation of collaborative working groups was recommended for consistency in methodologies and the possibility of combining data for future analyses. Regarding the causes of childhood leukaemia, major fields of research were discussed (environmental risk factors, genetics, infections, immunity, stem cells, experimental research). The need for multidisciplinary collaboration in developing research activities was underlined, including the prevalence of potential predisposition markers and investigating further the infectious aetiology hypothesis. Animal studies and genetic/epigenetic approaches appear of great interest. Routes for future research were pointed out.

miR-664 negatively regulates PLP2 and promotes cell proliferation and invasion in T-cell acute lymphoblastic leukaemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Hong; Miao, Mei-hua; Ji, Xue-qiang

2015-04-03

MicroRNAs (miRNAs) play important roles in the pathogenesis of many types of cancers by negatively regulating gene expression at posttranscriptional level. However, the role of microRNAs in leukaemia, particularly T-cell acute lymphoblastic leukaemia (T-ALL), has remained elusive. Here, we identified miR-664 and its predicted target gene PLP2 were differentially expressed in T-ALL using bioinformatics methods. In T-ALL cell lines, CCK-8 proliferation assay indicated that the cell proliferation was promoted by miR-664, while miR-664 inhibitor could significantly inhibited the proliferation. Moreover, migration and invasion assay showed that overexpression of miR-664 could significantly promoted the migration and invasion of T-ALL cells, whereasmore » miR-664 inhibitor could reduce cell migration and invasion. luciferase assays confirmed that miR-664 directly bound to the 3'untranslated region of PLP2, and western blotting showed that miR-664 suppressed the expression of PLP2 at the protein levels. This study indicated that miR-664 negatively regulates PLP2 and promotes proliferation and invasion of T-ALL cell lines. Thus, miR-664 may represent a potential therapeutic target for T-ALL intervention. - Highlights: • miR-664 mimics promote the proliferation and invasion of T-ALL cells. • miR-664 inhibitors inhibit the proliferation and invasion of T-ALL cells. • miR-664 targets 3′ UTR of PLP2 in T-ALL cells. • miR-664 negatively regulates PLP2 in T-ALL cells.« less

Violacein Induces Death of Resistant Leukaemia Cells via Kinome Reprogramming, Endoplasmic Reticulum Stress and Golgi Apparatus Collapse

PubMed Central

Queiroz, Karla C. S.; Milani, Renato; Ruela-de-Sousa, Roberta R.; Fuhler, Gwenny M.; Justo, Giselle Z.; Zambuzzi, Willian F.; Duran, Nelson; Diks, Sander H.; Spek, C. Arnold; Ferreira, Carmen V.; Peppelenbosch, Maikel P.

2012-01-01

It is now generally recognised that different modes of programmed cell death (PCD) are intimately linked to the cancerous process. However, the mechanism of PCD involved in cancer chemoprevention is much less clear and may be different between types of chemopreventive agents and tumour cell types involved. Therefore, from a pharmacological view, it is crucial during the earlier steps of drug development to define the cellular specificity of the candidate as well as its capacity to bypass dysfunctional tumoral signalling pathways providing insensitivity to death stimuli. Studying the cytotoxic effects of violacein, an antibiotic dihydro-indolone synthesised by an Amazon river Chromobacterium, we observed that death induced in CD34+/c-Kit+/P-glycoprotein+/MRP1+ TF1 leukaemia progenitor cells is not mediated by apoptosis and/or autophagy, since biomarkers of both types of cell death were not significantly affected by this compound. To clarify the working mechanism of violacein, we performed kinome profiling using peptide arrays to yield comprehensive descriptions of cellular kinase activities. Pro-death activity of violacein is actually carried out by inhibition of calpain and DAPK1 and activation of PKA, AKT and PDK, followed by structural changes caused by endoplasmic reticulum stress and Golgi apparatus collapse, leading to cellular demise. Our results demonstrate that violacein induces kinome reprogramming, overcoming death signaling dysfunctions of intrinsically resistant human leukaemia cells. PMID:23071514

Leukaemia cell of origin identified by chromatin landscape of bulk tumour cells

PubMed Central

George, Joshy; Uyar, Asli; Young, Kira; Kuffler, Lauren; Waldron-Francis, Kaiden; Marquez, Eladio; Ucar, Duygu; Trowbridge, Jennifer J.

2016-01-01

The precise identity of a tumour's cell of origin can influence disease prognosis and outcome. Methods to reliably define tumour cell of origin from primary, bulk tumour cell samples has been a challenge. Here we use a well-defined model of MLL-rearranged acute myeloid leukaemia (AML) to demonstrate that transforming haematopoietic stem cells (HSCs) and multipotent progenitors results in more aggressive AML than transforming committed progenitor cells. Transcriptome profiling reveals a gene expression signature broadly distinguishing stem cell-derived versus progenitor cell-derived AML, including genes involved in immune escape, extravasation and small GTPase signal transduction. However, whole-genome profiling of open chromatin reveals precise and robust biomarkers reflecting each cell of origin tested, from bulk AML tumour cell sampling. We find that bulk AML tumour cells exhibit distinct open chromatin loci that reflect the transformed cell of origin and suggest that open chromatin patterns may be leveraged as prognostic signatures in human AML. PMID:27397025

DNA-damage-induced differentiation of leukaemic cells as an anti-cancer barrier

PubMed Central

Santos, Margarida A.; Faryabi, Robert B.; Ergen, Aysegul V.; Day, Amanda M.; Malhowski, Amy; Canela, Andres; Onozawa, Masahiro; Lee, Ji-Eun; Callen, Elsa; Gutierrez-Martinez, Paula; Chen, Hua-Tang; Wong, Nancy; Finkel, Nadia; Deshpande, Aniruddha; Sharrow, Susan; Rossi, Derrick J.; Ito, Keisuke; Ge, Kai; Aplan, Peter D.; Armstrong, Scott A.; Nussenzweig, André

2015-01-01

Self-renewal is the hallmark feature both of normal stem cells and cancer stem cells1. Since the regenerative capacity of normal haematopoietic stem cells is limited by the accumulation of reactive oxygen species and DNA double-strand breaks2–4, we speculated that DNA damage might also constrain leukaemic self-renewal and malignant haematopoiesis. Here we show that the histone methyl-transferase MLL4, a suppressor of B-cell lymphoma5,6, is required for stem-cell activity and an aggressive form of acute myeloid leukaemia harbouring the MLL–AF9 oncogene. Deletion of MLL4 enhances myelopoiesis and myeloid differentiation of leukaemic blasts, which protects mice from death related to acute myeloid leukaemia. MLL4 exerts its function by regulating transcriptional programs associated with the antioxidant response. Addition of reactive oxygen species scavengers or ectopic expression of FOXO3 protects MLL4−/− MLL–AF9 cells from DNA damage and inhibits myeloid maturation. Similar to MLL4 deficiency, loss of ATM or BRCA1 sensitizes transformed cells to differentiation, suggesting that myeloid differentiation is promoted by loss of genome integrity. Indeed, we show that restriction-enzyme-induced double-strand breaks are sufficient to induce differentiation of MLL–AF9 blasts, which requires cyclin-dependent kinase inhibitor p21Cip1 (Cdkn1a) activity. In summary, we have uncovered an unexpected tumour-promoting role of genome guardians in enforcing the oncogene-induced differentiation blockade in acute myeloid leukaemia. PMID:25079327

Acute myeloid leukaemia: a paradigm for the clonal evolution of cancer?

PubMed Central

Grove, Carolyn S.; Vassiliou, George S.

2014-01-01

Acute myeloid leukaemia (AML) is an uncontrolled clonal proliferation of abnormal myeloid progenitor cells in the bone marrow and blood. Advances in cancer genomics have revealed the spectrum of somatic mutations that give rise to human AML and drawn our attention to its molecular evolution and clonal architecture. It is now evident that most AML genomes harbour small numbers of mutations, which are acquired in a stepwise manner. This characteristic, combined with our ability to identify mutations in individual leukaemic cells and our detailed understanding of normal human and murine haematopoiesis, makes AML an excellent model for understanding the principles of cancer evolution. Furthermore, a better understanding of how AML evolves can help us devise strategies to improve the therapy and prognosis of AML patients. Here, we draw from recent advances in genomics, clinical studies and experimental models to describe the current knowledge of the clonal evolution of AML and its implications for the biology and treatment of leukaemias and other cancers. PMID:25056697

Relationship between cytomegalovirus (CMV) reactivation, CMV-driven immunity, overall immune recovery and graft-versus-leukaemia effect in children.

PubMed

Jeljeli, Mohamed; Guérin-El Khourouj, Valérie; Porcher, Raphael; Fahd, Mony; Leveillé, Sandrine; Yakouben, Karima; Ouachée-Chardin, Marie; LeGoff, Jerome; Cordeiro, Debora Jorge; Pédron, Beatrice; Baruchel, Andre; Dalle, Jean-Hugues; Sterkers, Ghislaine

2014-07-01

The interplay between immune recovery, cytomegalovirus (CMV)-reactivation, CMV-driven immunity and graft-versus-leukaemia effect (GVL) was analysed in 108 children (median age: 8 years) who underwent haematopoietic-stem cell transplantation (HSCT) for acute leukaemia. Follow-up was 2 years unless death or relapse occurred. CMV-polymerase chain reaction (PCR) was programmed weekly until month +3 post-HSCT. Immunomonitoring consisted of sequential lymphocyte subset enumerations and analyses of T-cell proliferative and γ-interferon responses to CMV and to adenovirus. In the 108 recipients, the 2-year relapse rate (RR) was 25% (median time to onset 4·5 months; range: 24 d-17 months). CMV reactivation occurrence was 31% (median time to onset 26 d). Donor/recipient CMV serostatus did not influence RR. Among the 89 recipients disease-free after day +120, i) early CMV-reactivation before day +30 was more frequent (P = 0·01) in the relapse recipient group opposed to the non-relapse group. ii) CD8(+) /CD28(-) and CD4(+) CD45RA(-) T-cell expansions induced by CMV did not influence RR, iii) Recovery of anti-CMV and also anti-adenovirus immunity and of naïve CD4(+) T-cells was faster in the non-relapse group (P = 0·008; 0·009 and 0·002 respectively). In contrast to adult acute myeloid leukaemia, CMV reactivation was associated with increased RR in this paediatric series. Accelerated overall immune recovery rather than CMV-driven immunity had a favourable impact on RR. © 2014 John Wiley & Sons Ltd.

Characterization of the antiproliferative activity of Xylopia aethiopica

PubMed Central

2012-01-01

Background Xylopia aethiopica, a plant found throughout West Africa, has both nutritional and medicinal uses. The present study aims to characterize the effects of extracts of this plant on cancer cells. Results We report that X. aethiopica extract prepared with 70% ethanol has antiproliferative activity against a panel of cancer cell lines. The IC50 was estimated at 12 μg/ml against HCT116 colon cancer cells, 7.5 μg/ml and > 25 μg/ml against U937 and KG1a leukemia cells, respectively. Upon fractionation of the extract by HPLC, the active fraction induced DNA damage, cell cycle arrest in G1 phase and apoptotic cell death. By using NMR and mass spectrometry, we determined the structure of the active natural product in the HPLC fraction as ent-15-oxokaur-16-en-19-oic acid. Conclusion The main cytotoxic and DNA-damaging compound in ethanolic extracts of Xylopia aethiopica is ent-15-oxokaur-16-en-19-oic acid. PMID:22409878

Characterization of the antiproliferative activity of Xylopia aethiopica.

PubMed

Choumessi, Aphrodite T; Danel, Mathieu; Chassaing, Stefan; Truchet, Isabelle; Penlap, Véronique B; Pieme, Anatole Constant; Asonganyi, Tazoacha; Ducommun, Bernard; Valette, Annie

2012-03-12

Xylopia aethiopica, a plant found throughout West Africa, has both nutritional and medicinal uses. The present study aims to characterize the effects of extracts of this plant on cancer cells. We report that X. aethiopica extract prepared with 70% ethanol has antiproliferative activity against a panel of cancer cell lines. The IC50 was estimated at 12 μg/ml against HCT116 colon cancer cells, 7.5 μg/ml and > 25 μg/ml against U937 and KG1a leukemia cells, respectively. Upon fractionation of the extract by HPLC, the active fraction induced DNA damage, cell cycle arrest in G1 phase and apoptotic cell death. By using NMR and mass spectrometry, we determined the structure of the active natural product in the HPLC fraction as ent-15-oxokaur-16-en-19-oic acid. The main cytotoxic and DNA-damaging compound in ethanolic extracts of Xylopia aethiopica is ent-15-oxokaur-16-en-19-oic acid.

A Miniature Couette to Generate Shear for Flow Cytometry: Studying Real-Time Modulation of Intracellular Calcium in Monocytic Cells

PubMed Central

Zwartz, Gordon J.; Chigaev, Alexandre; Foutz, Terry D.; Edwards, Bruce; Sklar, Larry A.

2013-01-01

Extracellular hydrodynamic forces may be transmitted to the interior of cells through the alteration of integrin conformation and affinity. Integrin activation regulates leukocyte recruitment, cell activation, and transmigration. The cellular and molecular mechanisms for integrin activation are not precisely known, although intracellular calcium signaling is involved. Flow cytometry offers a versatile way to study intracellular calcium signaling in real-time. We report a novel method to generate defined shear by using a miniature Couette. Testing involved measuring shear induced intracellular calcium signals of human monoblastoid U937 cells in suspension. The Couette was connected externally to a flow cytometer and pressurized at 6 PSI (4.1 N/m2). Cells were subjected to well-defined shear between 0 and 1000 s−1 and delivered continuously within 10 s to a FACScan at 1 μl/s. Intracellular calcium levels and the percentage of cells activated increased as shear increased in duration and intensity. PMID:22045643

Acute myeloid leukemia-targeted toxin activates both apoptotic and necroptotic death mechanisms.

PubMed

Horita, Henrick; Frankel, Arthur E; Thorburn, Andrew

2008-01-01

Acute myelogenous leukemia (AML) is the second most common leukemia with approximately 13,410 new cases and 8,990 deaths annually in the United States. A novel fusion toxin treatment, diphtheria toxin GM-CSF (DT-GMCSF) has been shown to selectively eliminate leukemic repopulating cells that are critical for the formation of AML. We previously showed that DT-GMCSF treatment of U937 cells, an AML cell line, causes activation of caspases and the induction of apoptosis. In this study we further investigate the mechanisms of cell death induced by DT-GMCSF and show that, in addition to the activation of caspase-dependent apoptosis, DT-GMCSF also kills AML cells by simultaneously activating caspase-independent necroptosis. These mechanisms depend on the ability of the targeted toxin to inhibit protein synthesis, and are not affected by the receptor that is targeted or the mechanism through which protein synthesis is blocked. We conclude that fusion toxin proteins may be effective for treating AML cells whether or not they are defective in apoptosis.

Drosophila: a model for studying genetic and molecular aspects of haematopoiesis and associated leukaemias

PubMed Central

Crozatier, Michèle; Vincent, Alain

2011-01-01

Vertebrate haematopoietic stem cells (HSCs) give rise to a hierarchically organised set of progenitors for erythroid, myeloid, lymphoid and megakaryocyte lineages, and are responsible for lifelong maintenance of the blood system. Dysregulation of the haematopoietic differentiation programme is at the origin of numerous pathologies, including leukaemias. With the discoveries that many transcriptional regulators and signalling pathways controlling blood cell development are conserved between humans and Drosophila melanogaster, the fruit fly has become a good model for investigating the mechanisms underlying the generation of blood cell lineages and blood cell homeostasis. In this review article, we discuss how genetic and molecular studies of Drosophila haematopoiesis can contribute to our understanding of the haematopoietic niche, as well as of the origin and/or progression of haematopoietic malignancies in humans. PMID:21669932

Distinct homotypic B-cell receptor interactions shape the outcome of chronic lymphocytic leukaemia

PubMed Central

Minici, Claudia; Gounari, Maria; Übelhart, Rudolf; Scarfò, Lydia; Dühren-von Minden, Marcus; Schneider, Dunja; Tasdogan, Alpaslan; Alkhatib, Alabbas; Agathangelidis, Andreas; Ntoufa, Stavroula; Chiorazzi, Nicholas; Jumaa, Hassan; Stamatopoulos, Kostas; Ghia, Paolo; Degano, Massimo

2017-01-01

Cell-autonomous B-cell receptor (BcR)-mediated signalling is a hallmark feature of the neoplastic B lymphocytes in chronic lymphocytic leukaemia (CLL). Here we elucidate the structural basis of autonomous activation of CLL B cells, showing that BcR immunoglobulins initiate intracellular signalling through homotypic interactions between epitopes that are specific for each subgroup of patients with homogeneous clinicobiological profiles. The molecular details of the BcR–BcR interactions apparently dictate the clinical course of disease, with stronger affinities and longer half-lives in indolent cases, and weaker, short-lived contacts mediating the aggressive ones. The diversity of homotypic BcR contacts leading to cell-autonomous signalling reconciles the existence of a shared pathogenic mechanism with the biological and clinical heterogeneity of CLL and offers opportunities for innovative treatment strategies. PMID:28598442

Anti-inflammatory steroidal glycosides from the berries of Solanum nigrum L. (European black nightshade).

PubMed

Xiang, Limin; Wang, Yihai; Yi, Xiaomin; He, Xiangjiu

2018-04-01

Seven previously undescribed steroidal glycosides, along with three known congeners were isolated from the unripe berries of Solanum nigrum L. (Solanaceae). Their structures were elucidated on basis of 1D and 2D NMR, HR-ESI-MS spectroscopic data and GC analysis after acid hydrolysis. The potential inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide in RAW 264.7 cell line and the anti-proliferative activities against five cancer cell lines (HL-60, U-937, Jurkat, K562 and HepG2) were evaluated. Seven compounds exhibited inhibition activities on NO production with IC 50 values ranging from 11.33 to 49.35 μM. Structure-activity relationships of the isolated compounds were also discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Targeted therapy with MXD3 siRNA, anti-CD22 antibody and nanoparticles for precursor B-cell acute lymphoblastic leukaemia.

PubMed

Satake, Noriko; Duong, Connie; Chen, Cathy; Barisone, Gustavo A; Diaz, Elva; Tuscano, Joseph; Rocke, David M; Nolta, Jan; Nitin, Nitin

2014-11-01

Conventional chemotherapy for precursor B-cell (preB) acute lymphoblastic leukaemia (ALL) has limitations that could be overcome by targeted therapy. Previously, we discovered a potential therapeutic molecular target, MDX3 (MAX dimerization protein 3), in preB ALL. In this study, we hypothesize that an effective siRNA therapy for preB ALL can be developed using antiCD22 antibody (αCD22 Ab) and nanoparticles. We composed nanocomplexes with super paramagnetic iron oxide nanoparticles (SPIO NPs), αCD22 Abs and MXD3 siRNA molecules based on physical interactions between the molecules. We demonstrated that the MXD3 siRNA-αCD22 Ab-SPIO NP complexes entered leukaemia cells and knocked down MXD3, leading the cells to undergo apoptosis and resulting in decreased live cell counts in the cell line Reh and in primary preB ALL samples in vitro. Furthermore, the cytotoxic effects of the MXD3 siRNA-αCD22 Ab-SPIO NP complexes were significantly enhanced by addition of the chemotherapy drugs vincristine or doxorubicin. We also ruled out potential cytotoxic effects of the MXD3 siRNA-αCD22 Ab-SPIO NP complexes on normal primary haematopoietic cells. Normal B cells were affected while CD34-positive haematopoietic stem cells and non-B cells were not. These data suggest that MXD3 siRNA-αCD22 Ab-SPIO NP complexes have the potential to be a new targeted therapy for preB ALL. © 2014 John Wiley & Sons Ltd.

Therapy targets in glioblastoma and cancer stem cells: lessons from haematopoietic neoplasms

PubMed Central

Cruceru, Maria Linda; Neagu, Monica; Demoulin, Jean-Baptiste; Constantinescu, Stefan N

2013-01-01

Despite intense efforts to identify cancer-initiating cells in malignant brain tumours, markers linked to the function of these cells have only very recently begun to be uncovered. The notion of cancer stem cell gained prominence, several molecules and signalling pathways becoming relevant for diagnosis and treatment. Whether a substantial fraction or only a tiny minority of cells in a tumor can initiate and perpetuate cancer, is still debated. The paradigm of cancer-initiating stem cells has initially been developed with respect to blood cancers where chronic conditions such as myeloproliferative neoplasms are due to mutations acquired in a haematopoietic stem cell (HSC), which maintains the normal hierarchy to neoplastic haematopoiesis. In contrast, acute leukaemia transformation of such blood neoplasms appears to derive not only from HSCs but also from committed progenitors that cannot differentiate. This review will focus on putative novel therapy targets represented by markers described to define cancer stem/initiating cells in malignant gliomas, which have been called ‘leukaemia of the brain’, given their rapid migration and evolution. Parallels are drawn with other cancers, especially haematopoietic, given the similar rampant proliferation and treatment resistance of glioblastoma multiforme and secondary acute leukaemias. Genes associated with the malignant conditions and especially expressed in glioma cancer stem cells are intensively searched. Although many such molecules might only coincidentally be expressed in cancer-initiating cells, some may function in the oncogenic process, and those would be the prime candidates for diagnostic and targeted therapy. For the latter, combination therapies are likely to be envisaged, given the robust and plastic signalling networks supporting malignant proliferation. PMID:23998913

Case of relentless chronic phase of chronic myeloid leukaemia.

PubMed

Chan, Onyee; Chen, Hao; Krishnadasan, Ravitharan; Anwer, Faiz

2016-06-22

Initial treatment of chronic phase chronic myeloid leukaemia is straightforward in today's era of tyrosine kinase inhibitors. However, managing refractory cases remain a major challenge due to the multiple factors that can influence decision-making, including medication tolerance, disease burden, mutation status, comorbidities, availability of donor, and fitness for an ablative conditioning. We report a male patient presenting with chronic phase chronic myeloid leukaemia who was treated with 5 different tyrosine kinase inhibitors either due to intolerance and/or failed response. He subsequently received 2 haploidentical haematopoietic stem cells transplants before achieving complete remission. This case highlights various treatment options, need for vigilant disease monitoring, and the possibility of complete positive response even after many lines of therapy failure. 2016 BMJ Publishing Group Ltd.

CCR4 frameshift mutation identifies a distinct group of adult T cell leukaemia/lymphoma with poor prognosis.

PubMed

Yoshida, Noriaki; Miyoshi, Hiroaki; Kato, Takeharu; Sakata-Yanagimoto, Mamiko; Niino, Daisuke; Taniguchi, Hiroaki; Moriuchi, Yukiyoshi; Miyahara, Masaharu; Kurita, Daisuke; Sasaki, Yuya; Shimono, Joji; Kawamoto, Keisuke; Utsunomiya, Atae; Imaizumi, Yoshitaka; Seto, Masao; Ohshima, Koichi

2016-04-01

Adult T cell leukaemia/lymphoma (ATLL) is an intractable T cell neoplasm caused by human T cell leukaemia virus type 1. Next-generation sequencing-based comprehensive mutation studies have revealed recurrent somatic CCR4 mutations in ATLL, although clinicopathological findings associated with CCR4 mutations remain to be delineated. In the current study, 184 cases of peripheral T cell lymphoma, including 113 cases of ATLL, were subjected to CCR4 mutation analysis. This sequence analysis identified mutations in 27% (30/113) of cases of ATLL and 9% (4/44) of cases of peripheral T cell lymphoma not otherwise specified. Identified mutations included nonsense (NS) and frameshift (FS) mutations. No significant differences in clinicopathological findings were observed between ATLL cases stratified by presence of CCR4 mutation. All ATLL cases with CCR4 mutations exhibited cell-surface CCR4 positivity. Semi-quantitative CCR4 protein analysis of immunohistochemical sections revealed higher CCR4 expression in cases with NS mutations of CCR4 than in cases with wild-type (WT) CCR4. Furthermore, among ATLL cases, FS mutation was significantly associated with a poor prognosis, compared with NS mutation and WT CCR4. These results suggest that CCR4 mutation is an important determinant of the clinical course in ATLL cases, and that NS and FS mutations of CCR4 behave differently with respect to ATLL pathophysiology. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Dipeptide species regulate p38MAPK–Smad3 signalling to maintain chronic myelogenous leukaemia stem cells

PubMed Central

Naka, Kazuhito; Jomen, Yoshie; Ishihara, Kaori; Kim, Junil; Ishimoto, Takahiro; Bae, Eun-Jin; Mohney, Robert P.; Stirdivant, Steven M.; Oshima, Hiroko; Oshima, Masanobu; Kim, Dong-Wook; Nakauchi, Hiromitsu; Takihara, Yoshihiro; Kato, Yukio; Ooshima, Akira; Kim, Seong-Jin

2015-01-01

Understanding the specific survival of the rare chronic myelogenous leukaemia (CML) stem cell population could provide a target for therapeutics aimed at eradicating these cells. However, little is known about how survival signalling is regulated in CML stem cells. In this study, we survey global metabolic differences between murine normal haematopoietic stem cells (HSCs) and CML stem cells using metabolomics techniques. Strikingly, we show that CML stem cells accumulate significantly higher levels of certain dipeptide species than normal HSCs. Once internalized, these dipeptide species activate amino-acid signalling via a pathway involving p38MAPK and the stemness transcription factor Smad3, which promotes CML stem cell maintenance. Importantly, pharmacological inhibition of dipeptide uptake inhibits CML stem cell activity in vivo. Our results demonstrate that dipeptide species support CML stem cell maintenance by activating p38MAPK–Smad3 signalling in vivo, and thus point towards a potential therapeutic target for CML treatment. PMID:26289811

Human retroviruses in leukaemia and AIDS: reflections on their discovery, biology and epidemiology.

PubMed

Karpas, Abraham

2004-11-01

The study of retroviruses has had a profound impact by unveiling an unusual form of viral replication: the multiplication of RNA viruses via a proviral DNA, for which Jan Svoboda provided the experimental model over forty years ago. In 1970 Temin, Mizutani and Baltimore discovered that this group of viruses contains a unique enzyme catalysing the synthesis of a DNA copy of the viral RNA: reverse transcriptase (RT). The discovery of RT has itself had an enormous impact on molecular biology in general, but also stimulated many premature claims of its detection in human disease. Claims by Gallo's laboratory that the cytoplasm of human leukaemia cells contained RT proved to be unfounded, as did his report in collaboration with Weiss that myeloid leukaemia contained HL23 virus, this organism proving not to be human but a laboratory contaminant of three monkey viruses. Conclusive demonstration of a retroviral involvement in human leukaemia was first provided in 1981 by Hinuma and his associates, showing that adult T-cell leukaemia (ATL), a rare form of leukaemia endemic to south-west Japan, is caused by a new retrovirus (ATLV). Other publications in December 1980 and through 1981 claimed the discovery of a new human T-cell leukaemia virus involved in mycosis fungoides (MF) and Sézary's syndrome (SS). This virus was termed HTLV by Gallo. The nucleotide sequence of ATLV is strongly conserved, that of my 1983 isolate from a black British ATL patient being practically identical with the Japanese virus isolates. After AIDS was recognised in 1981 by Gottlieb and coworkers as a new human disease, several papers were published by Gallo and his associates during 1983-4, invoking the oncovirus responsible for adult T-cell leukaemia as the cause of AIDS. In 1983 the French scientist Barré-Sinoussi and her colleagues succeeded in isolating a new agent in the disease, a lentivirus, which they named LAV. The French immunologist Klatzmann and his colleagues discovered that LAV killed CD4+ T-cells, furnishing an explanation for the pathogenesis of AIDS and providing a mechanism for how AIDS developed. For some time Gallo continued to suggest leukaemia virus involvement, claiming that his independent isolate of the AIDS virus, termed HTLV-III, was closely related to HTLV-I (the Japanese ATLV). Although this created considerable confusion among researchers for a period, the relationship was eventually disproved. Unlike ATLV, whose nucleic acid sequence is very stable, the AIDS virus (now termed HIV by international agreement) is extraordinarily unstable, the sequences of independent HIV isolates being quite unique: this made it possible to establish conclusively that both HTLV-III and another independent isolate CBL-1, from Weiss' laboratory, were actually LAV isolates from the French laboratory. It has been shown by Hayami and his associates that only African primates are infected with similar lentiviruses to HIV which explains why AIDS started in Africa. Further research has clarified the origin of HIV-1 to be a chimpanzee lentivirus and HIV-2 to be the sooty mangabey lentivirus, which began to spread in humans perhaps no more than fifty years ago. The infection has spread rapidly, primarily through sexual intercourse, but also by transmission through blood and its products as well as contaminated needles and syringes. Sexual intercourse has now spread the virus around the World; and there are probably some 70 million infected. 90% of those infected with HIV develop the deadly disease of AIDS within ten years of infection: the death toll from the disease has been enormous. By contrast, HTLV-1 has been infecting man in isolated areas probably for hundreds of years; but it has not spread widely. HTLV causes leukaemia in only less than 1% of those infected. The prime mode of transmission of HTLV-1 is between mother and neonate; infections can be reduced by stopping breast-feeding by infected mothers. The isolation of HIV enabled screening tests to be developed for contaminated blood. However, due to the peculiar biology of HIV infection, unfortunately all efforts to develop an effective vaccine have so far failed.

Instruction of haematopoietic lineage choices, evolution of transcriptional landscapes and cancer stem cell hierarchies derived from an AML1-ETO mouse model

PubMed Central

Cabezas-Wallscheid, Nina; Eichwald, Victoria; de Graaf, Jos; Löwer, Martin; Lehr, Hans-Anton; Kreft, Andreas; Eshkind, Leonid; Hildebrandt, Andreas; Abassi, Yasmin; Heck, Rosario; Dehof, Anna Katharina; Ohngemach, Svetlana; Sprengel, Rolf; Wörtge, Simone; Schmitt, Steffen; Lotz, Johannes; Meyer, Claudius; Kindler, Thomas; Zhang, Dong-Er; Kaina, Bernd; Castle, John C; Trumpp, Andreas; Sahin, Ugur; Bockamp, Ernesto

2013-01-01

The t(8;21) chromosomal translocation activates aberrant expression of the AML1-ETO (AE) fusion protein and is commonly associated with core binding factor acute myeloid leukaemia (CBF AML). Combining a conditional mouse model that closely resembles the slow evolution and the mosaic AE expression pattern of human t(8;21) CBF AML with global transcriptome sequencing, we find that disease progression was characterized by two principal pathogenic mechanisms. Initially, AE expression modified the lineage potential of haematopoietic stem cells (HSCs), resulting in the selective expansion of the myeloid compartment at the expense of normal erythro- and lymphopoiesis. This lineage skewing was followed by a second substantial rewiring of transcriptional networks occurring in the trajectory to manifest leukaemia. We also find that both HSC and lineage-restricted granulocyte macrophage progenitors (GMPs) acquired leukaemic stem cell (LSC) potential being capable of initiating and maintaining the disease. Finally, our data demonstrate that long-term expression of AE induces an indolent myeloproliferative disease (MPD)-like myeloid leukaemia phenotype with complete penetrance and that acute inactivation of AE function is a potential novel therapeutic option. PMID:24124051

Age-related clinical and biological features of PTEN abnormalities in T-cell acute lymphoblastic leukaemia.

PubMed

Tesio, M; Trinquand, A; Ballerini, P; Hypolite, G; Lhermitte, L; Petit, A; Ifrah, N; Baruchel, A; Dombret, H; Macintyre, E; Asnafi, V

2017-12-01

The tumour suppressor gene PTEN is commonly altered in T-cell acute lymphoblastic leukaemia but its prognostic impact is still debated. We screened a cohort of 573 fully characterised adult and paediatric T-cell acute lymphoblastic leukaemia (T-ALL) patients for genomic PTEN abnormalities. PTEN-inactivating mutations and/or deletions were identified in 91 cases (16%), including 18% of paediatric (49/277) and 14% of adult cases (42/296). Thirty-four patients harboured only mutations, 12 cases demonstrated only large deletions and 9 only microdeletions. About 36 patients had combined alterations. Different mechanisms of PTEN inactivation predicted differences in the clinical outcome for both adult and paediatric patients treated according to the GRAALL03/05 and FRALLE2000 protocols. Whereas large deletions predicted lower 5-year overall survival (P=0.0053 in adults, P=0.001 in children) and disease-free survival (P=0.0009 in adults, P=0.0002 in children), mutations were not associated with a worse prognosis. The prognostic impact of PTEN loss is therefore linked to the underlying type of genomic abnormality, both in adult and paediatric T-ALLs, demonstrating that detailed analysis of the type of abnormality type would be useful to refine risk stratification.

AML1-ETO requires enhanced C/D box snoRNA/RNP formation to induce self-renewal and leukaemia.

PubMed

Zhou, Fengbiao; Liu, Yi; Rohde, Christian; Pauli, Cornelius; Gerloff, Dennis; Köhn, Marcel; Misiak, Danny; Bäumer, Nicole; Cui, Chunhong; Göllner, Stefanie; Oellerich, Thomas; Serve, Hubert; Garcia-Cuellar, Maria-Paz; Slany, Robert; Maciejewski, Jaroslaw P; Przychodzen, Bartlomiej; Seliger, Barbara; Klein, Hans-Ulrich; Bartenhagen, Christoph; Berdel, Wolfgang E; Dugas, Martin; Taketo, Makoto Mark; Farouq, Daneyal; Schwartz, Schraga; Regev, Aviv; Hébert, Josée; Sauvageau, Guy; Pabst, Caroline; Hüttelmaier, Stefan; Müller-Tidow, Carsten

2017-07-01

Leukaemogenesis requires enhanced self-renewal, which is induced by oncogenes. The underlying molecular mechanisms remain incompletely understood. Here, we identified C/D box snoRNAs and rRNA 2'-O-methylation as critical determinants of leukaemic stem cell activity. Leukaemogenesis by AML1-ETO required expression of the groucho-related amino-terminal enhancer of split (AES). AES functioned by inducing snoRNA/RNP formation via interaction with the RNA helicase DDX21. Similarly, global loss of C/D box snoRNAs with concomitant loss of rRNA 2'-O-methylation resulted in decreased leukaemia self-renewal potential. Genomic deletion of either C/D box snoRNA SNORD14D or SNORD35A suppressed clonogenic potential of leukaemia cells in vitro and delayed leukaemogenesis in vivo. We further showed that AML1-ETO9a, MYC and MLL-AF9 all enhanced snoRNA formation. Expression levels of C/D box snoRNAs in AML patients correlated closely with in vivo frequency of leukaemic stem cells. Collectively, these findings indicate that induction of C/D box snoRNA/RNP function constitutes an important pathway in leukaemogenesis.

The Cks1/Cks2 axis fine-tunes Mll1 expression and is crucial for MLL-rearranged leukaemia cell viability.

PubMed

Grey, William; Ivey, Adam; Milne, Thomas A; Haferlach, Torsten; Grimwade, David; Uhlmann, Frank; Voisset, Edwige; Yu, Veronica

2018-01-01

The Cdc28 protein kinase subunits, Cks1 and Cks2, play dual roles in Cdk-substrate specificity and Cdk-independent protein degradation, in concert with the E3 ubiquitin ligase complexes SCF Skp2 and APC Cdc20 . Notable targets controlled by Cks include p27 and Cyclin A. Here, we demonstrate that Cks1 and Cks2 proteins interact with both the Mll N and Mll C subunits of Mll1 (Mixed-lineage leukaemia 1), and together, the Cks proteins define Mll1 levels throughout the cell cycle. Overexpression of CKS1B and CKS2 is observed in multiple human cancers, including various MLL-rearranged (MLLr) AML subtypes. To explore the importance of MLL-Fusion Protein regulation by CKS1/2, we used small molecule inhibitors (MLN4924 and C1) to modulate their protein degradation functions. These inhibitors specifically reduced the proliferation of MLLr cell lines compared to primary controls. Altogether, this study uncovers a novel regulatory pathway for MLL1, which may open a new therapeutic approach to MLLr leukaemia. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Clinical utility of next-generation sequencing-based minimal residual disease in paediatric B-cell acute lymphoblastic leukaemia.

PubMed

Sekiya, Yuko; Xu, Yinyan; Muramatsu, Hideki; Okuno, Yusuke; Narita, Atsushi; Suzuki, Kyogo; Wang, Xinan; Kawashima, Nozomu; Sakaguchi, Hirotoshi; Yoshida, Nao; Hama, Asahito; Takahashi, Yoshiyuki; Kato, Koji; Kojima, Seiji

2017-01-01

We assessed the clinical utility of next-generation sequencing (NGS)-based monitoring of minimal residual disease (MRD) in a uniformly treated cohort of 79 patients with paediatric B-cell acute lymphoblastic leukaemia. Bone marrow samples were collected at the time of diagnosis, days 33 and 80, pre- (4-5 months) and post- (24 months) maintenance therapy time points, and at relapse. We identified leukaemia-specific CDR3 sequences in 72 of 79 patients (91%) and detected MRD in 59 of 232 samples. Although MRD was detected in 28 of 55 samples (51%) on day 33, the frequencies of MRD detection decreased to 25% (16/65) at day 80, 19% (11/58) at 4-5 months and 7·4% (4/54) at 24 months. In a univariate analysis, positive MRD results on day 80 [relative risk (RR) 95% confidence interval (CI) = 7·438 (2·561-21·6), P < 0·001], at 4-5 months [RR (95% CI) = 10·24 (3·374-31·06), P < 0·001], and at 24 months [RR (95% CI) = 19·26 (4·974-74·59), P < 0·001] exhibited statistically significant associations with inferior leukaemia-free survival; this was confirmed using a Cox proportional hazard model. Our study suggests the promising potential of NGS-MRD for patients with B-cell ALL. © 2016 John Wiley & Sons Ltd.

Safety and activity of blinatumomab for adult patients with relapsed or refractory B-precursor acute lymphoblastic leukaemia: a multicentre, single-arm, phase 2 study.

PubMed

Topp, Max S; Gökbuget, Nicola; Stein, Anthony S; Zugmaier, Gerhard; O'Brien, Susan; Bargou, Ralf C; Dombret, Hervé; Fielding, Adele K; Heffner, Leonard; Larson, Richard A; Neumann, Svenja; Foà, Robin; Litzow, Mark; Ribera, Josep-Maria; Rambaldi, Alessandro; Schiller, Gary; Brüggemann, Monika; Horst, Heinz A; Holland, Chris; Jia, Catherine; Maniar, Tapan; Huber, Birgit; Nagorsen, Dirk; Forman, Stephen J; Kantarjian, Hagop M

2015-01-01

Adults with relapsed or refractory B-precursor acute lymphoblastic leukaemia have an unfavourable prognosis. Blinatumomab is a bispecific T-cell engager antibody construct targeting CD19, an antigen consistently expressed on B-lineage acute lymphoblastic leukaemia cells. We aimed to confirm the activity and safety profile of blinatumomab for acute lymphoblastic leukaemia. In a multicentre, single-arm, open-label phase 2 study, we enrolled adult patients with Philadelphia-chromosome-negative, primary refractory or relapsed (first relapse within 12 months of first remission, relapse within 12 months after allogeneic haemopoietic stem-cell transplantation [HSCT], or no response to or relapse after first salvage therapy or beyond) leukaemia. Patients received blinatumomab (9 μg/day for the first 7 days and 28 μg/day thereafter) by continuous intravenous infusion over 4 weeks every 6 weeks (up to five cycles), per protocol. The primary endpoint was complete remission (CR) or CR with partial haematological recovery of peripheral blood counts (CRh) within the first two cycles. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT01466179. Between Jan 13, 2012, and Oct 10, 2013, 189 patients were enrolled and treated with blinatumomab. After two cycles, 81 (43%, 95% CI 36-50) patients had achieved a CR or CRh: 63 (33%) patients had a CR and 18 (10%) patients had a CRh. 32 (40%) of patients who achieved CR/CRh underwent subsequent allogeneic HSCT. The most frequent grade 3 or worse adverse events were febrile neutropenia (48 patients, 25%), neutropenia (30 patients, 16%), and anaemia (27 patients, 14%). Three (2%) patients had grade 3 cytokine release syndrome. Neurologic events of worst grade 3 or 4 occurred in 20 (11%) and four (2%) patients, respectively. Three deaths (due to sepsis, Escherichia coli sepsis, and Candida infection) were thought to be treatment-related by the investigators. Single-agent blinatumomab showed antileukaemia activity in adult patients with relapsed or refractory B-precursor acute lymphoblastic leukaemia characterised by negative prognostic factors. Further assessment of blinatumomab treatment earlier in the course of the disease and in combination with other treatment approaches is warranted. Amgen. Copyright © 2015 Elsevier Ltd. All rights reserved.

History of Maternal Fetal Loss and Childhood Leukaemia Risk in Subsequent Offspring: Differentials by Miscarriage or Stillbirth History and Disease Subtype.

PubMed

Karalexi, M A; Skalkidou, A; Thomopoulos, T P; Belechri, M; Biniaris-Georgallis, S-I; Bouka, E; Baka, M; Hatzipantelis, E; Kourti, M; Polychronopoulou, S; Sidi, V; Stiakaki, E; Moschovi, M; Dessypris, N; Petridou, E Th

2015-09-01

Despite the putative intrauterine origins of childhood (0-14 years) leukaemia, it is complex to assess the impact of perinatal factors on disease onset. Results on the association of maternal history of fetal loss (miscarriage/stillbirth) with specific disease subtypes in the subsequent offspring are in conflict. We sought to investigate whether miscarriage and stillbirth may have different impacts on the risk of acute lymphoblastic leukaemia (ALL) and of its main immunophenotypes (B-cell and T-cell ALL), as contrasted to acute myeloid leukaemia (AML). One thousand ninety-nine ALL incidents (957 B-ALL) and 131 AML cases along with 1:1 age and gender-matched controls derived from the Nationwide Registry for Childhood Hematological Malignancies and Brain Tumors (1996-2013) were studied. Multivariable regression models were used to assess the roles of previous miscarriage(s) and stillbirth(s) on ALL (overall, B-, T-ALL) and AML, controlling for potential confounders. Statistically significant exposure and disease subtype-specific associations of previous miscarriage(s) exclusively with AML [odds ratio (OR) 1.67, 95% confidence interval (CI) 1.00, 2.81] and stillbirth(s) with ALL [OR 4.82, 95% CI 1.63, 14.24] and B-ALL particularly, emerged. Differential pathophysiological pathways pertaining to genetic polymorphisms or cytogenetic aberrations are likely to create hostile environments leading either to fetal loss or the development of specific leukaemia subtypes in subsequent offspring, notably distinct associations of maternal miscarriage history confined to AML and stillbirth history confined to ALL (specifically B-ALL). If confirmed and further supported by studies revealing underlying mechanisms, these results may shed light on the divergent leukemogenesis processes. © 2015 John Wiley & Sons Ltd.

Aberrant glycosylation of plasma proteins in severe preeclampsia promotes monocyte adhesion.

PubMed

Flood-Nichols, Shannon K; Kazanjian, Avedis A; Tinnemore, Deborah; Gafken, Philip R; Ogata, Yuko; Napolitano, Peter G; Stallings, Jonathan D; Ippolito, Danielle L

2014-02-01

Glycosylation of plasma proteins increases during pregnancy. Our objectives were to investigate an anti-inflammatory role of these proteins in normal pregnancies and determine whether aberrant protein glycosylation promotes monocyte adhesion in preeclampsia. Plasma was prospectively collected from nonpregnant controls and nulliparous patients in all 3 trimesters. Patients were divided into cohorts based on the applicable postpartum diagnosis. U937 monocytes were preconditioned with enzymatically deglycosylated plasma, and monocyte adhesion to endothelial cell monolayers was quantified by spectrophotometry. Plasma from nonpregnant controls, first trimester normotensives, and first trimester patients with mild preeclampsia inhibited monocyte-endothelial cell adhesion (P < .05), but plasma from first trimester patients with severe preeclampsia and second and third trimester normotensives did not. Deglycosylating plasma proteins significantly increased adhesion in all the cohorts. These results support a role of plasma glycoprotein interaction in monocyte-endothelial cell adhesion and could suggest a novel therapeutic target for severe preeclampsia.

Ethanol extracts of black pepper or turmeric down-regulated SIRT1 protein expression in Daudi culture cells.

PubMed

Nishimura, Yuri; Kitagishi, Yasuko; Yoshida, Hitomi; Okumura, Naoko; Matsuda, Satoru

2011-01-01

SIRT1 is a mammalian candidate molecule involved in longevity and diverse metabolic processes. The present study aimed to determine the effects of certain herbs and spices on SIRT1 expression. Human cell lines Daudi, Jurkat, U937 and K562 were cultured in RPMI-1640. Herb and spice powders were prepared and the supernatants were collected. RT-PCR was used to quantify the expression level of the gene. Protein samples were then analyzed by Western blotting. Western blotting revealed the down-regulation of SIRT1 protein expression in Daudi cells treated with extracts of black pepper or turmeric. On the other hand, the effect on the SIRT1 gene expression examined by reverse transcription polymerase chain reaction was unaltered. In conclusion, component(s) of certain herbs and spices may induce the down-regulation of SIRT1 protein.

The BTK Inhibitor Ibrutinib (PCI-32765) Blocks Hairy Cell Leukaemia Survival, Proliferation and BCR Signalling: A New Therapeutic Approach

PubMed Central

Sivina, Mariela; Kreitman, Robert J.; Arons, Evgeny; Ravandi, Farhad; Burger, Jan A.

2014-01-01

B cell receptor (BCR) signalling plays a critical role in the progression of several B-cell malignancies, but its role in hairy cell leukaemia (HCL) is ambiguous. Bruton tyrosine kinase (BTK), a key player in BCR signalling, migration and adhesion, can be targeted with ibrutinib, a selective, irreversible BTK inhibitor. We analysed BTK expression and function in HCL and analysed the effects of ibrutinib on HCL cells. We demonstrated uniform BTK protein expression in HCL cells. Ibrutinib significantly inhibited HCL proliferation and cell cycle progression. Accordingly, ibrutinib also reduced HCL cell survival after BCR triggering with anti-immunoglobulins (A, G, and M) and abrogated the activation of kinases downstream of the BCR (PI3K and MAPK). Ibrutinib also inhibited BCR-dependent secretion of the chemokines CCL3 and CCL4 by HCL cells. Interestingly, ibrutinib inhibited CXCL12-induced signalling, a key pathway for bone marrow homing. Collectively, our data support the clinical development of ibrutinib in patients with HCL. PMID:24697238

A new respirometric endpoint-based biosensor to assess the relative toxicity of chemicals on immobilized human cells.

PubMed

Dragone, Roberto; Frazzoli, Chiara; Grappelli, Claudio; Campanella, Luigi

2009-01-01

Several functional and biochemical parameters have been proposed as biomarkers of effect of environmental pollutants. A rapid biosensor working with immobilized human U-937 cells was developed and applied to environmentally relevant chemicals with different structures and toxicological pathways, i.e. benzalkonium chloride, clofibric acid, diclofenac, mercury nitrate, ofloxacin, and sodium dodecyl sulphate. Respiration of cells was relied upon as a comprehensive biochemical effect for screening purposes. Analytical parameter (DeltappmO(2)) and toxicological index (respiratory inhibition, delta%) measured after 1h of exposure were utilized for dose-response relationship study. Results (toxicity rating scales based on delta(50)% and steepness) were compared with those obtained by the same approach previously optimized on Saccharomyces cerevisiae. The toxicity rating scale obtained by the biomarker based on human mitochondrial and cell metabolic activities compared well with previous scale obtained on yeast cells and with available in-vivo acute toxicity indexes; respiration was confirmed as toxicological endpoint reliably measurable by the biosensor.

Expression of allograft inflammatory factor-1 in inflammatory skin disorders.

PubMed

Orsmark, Christina; Skoog, Tiina; Jeskanen, Leila; Kere, Juha; Saarialho-Kere, Ulpu

2007-01-01

Allograft inflammatory factor-1 (AIF-1) is an evolutionarily conserved, inflammatory protein produced by activated macrophages during chronic transplant rejection and in inflammatory brain lesions. Since T-cell-mediated inflammation is common to various dermatoses and nothing is known about AIF-1 in skin, we studied its protein expression at the tissue level and regulation in monocytic cell lines by various agents. Using immunohistochemistry, we found that AIF-1 is expressed at low levels in normal skin, but is highly upregulated in various inflammatory skin disorders, such as psoriasis, lichen planus, graft-versus-host disease and mycosis fungoides. The main cell types expressing AIF-1 in affected skin are macrophages and Langerhans' cells. We also show by real-time PCR that AIF-1 mRNA levels in monocytic THP-1 and U937 cell lines are significantly upregulated by retinoic acid as well as a number of cytokines. We conclude that AIF-1 may mediate survival and pro-inflammatory properties of macrophages in skin diseases.

SERUM metabolomics of acute lymphoblastic leukaemia and acute myeloid leukaemia for probing biomarker molecules.

PubMed

Musharraf, Syed Ghulam; Siddiqui, Amna Jabbar; Shamsi, Tahir; Naz, Arshi

2017-12-01

Acute leukaemia (AL) is a critical neoplasm of white blood cells. Diagnosing AL requires bone marrow puncture procedure, which many patients do not consent to for it is invasive. Hence sensitive and specific early diagnostic biomarkers are essential for non-invasive diagnosis, new therapeutics and improving the disease prognosis. To differentiate the metabolic alterations associated with acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML), we investigated serum of ALL and AML patients in comparison with two controls using gas chromatography coupled with triple quadrupole tandem mass spectrometry and multivariate statistical analysis. Twenty seven out of 1425 metabolites were found differentiative among ALL, AML, aplastic anaemia (APA) patients and healthy control using p-value ≤ 0.001. ALL is the most dissimilar group from other three groups as in hierarchical clustering showed 72.1% dissimilarity. Model generation using PLSDA gave an overall accuracy of 91.9%. This study helps in metabolic fingerprinting of control and disease serum at high significance levels and could be used for early diagnosing of AL. Based on pathways analysis, fatty acid metabolism is deregulated in patients with AL and may represent an underlying metabolic pathway associated with disease progression. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Role of Bruton's tyrosine kinase inhibitors in HIV-1-infected cells.

PubMed

Guendel, Irene; Iordanskiy, Sergey; Sampey, Gavin C; Van Duyne, Rachel; Calvert, Valerie; Petricoin, Emanuel; Saifuddin, Mohammed; Kehn-Hall, Kylene; Kashanchi, Fatah

2015-06-01

Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high-throughput proteomic assays, we have previously identified Bruton's tyrosine kinase (BTK) as a host protein that was uniquely upregulated in the plasma membrane of human immunodeficiency virus (HIV-1)-infected T cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant upregulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells; however, new BTK protein complexes were identified and distributed in both high molecular weight (∼600 kDa) and a small molecular weight complex (∼60-120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1-infected cells using small interfering RNA (siRNA) resulted in selective death of infected, but not uninfected, cells. Using BTK-specific antibody and small-molecule inhibitors including LFM-A13 and a FDA-approved compound, ibrutinib (PCI-32765), we have found that HIV-1-infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1-infected cells are sensitive to treatments targeting BTK expressed in infected cells.

Role of Bruton’s Tyrosine Kinase inhibitors in HIV-1 infected cells

PubMed Central

Guendel, Irene; Iordanskiy, Sergey; Sampey, Gavin C; Van Duyne, Rachel; Calvert, Valerie; Petricoin, Emanuel; Saifuddin, Mohammed; Kehn-Hall, Kylene; Kashanchi, Fatah

2015-01-01

Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high throughput proteomic assays, we have previously identified Bruton’s tyrosine kinase (BTK) as a host protein that was uniquely up-regulated in the plasma membrane of HIV-1 infected T-cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant up-regulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells, however new BTK protein complexes were identified and distributed in both high molecular weight (~600 kDa) and a small molecular weight complex (~60–120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1 infected cells using siRNA resulted in selective death of infected, but not uninfected, cells. Using BTK specific antibody and small molecule inhibitors including LFM-A13 and a FDA approved compound, Ibrutinib (PCI – 32765), we have found that HIV-1 infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1 infected cells are sensitive to treatments targeting BTK expressed in infected cells. PMID:25672887

Non-tumour bone marrow lymphocytes correlate with improved overall survival in childhood acute lymphoblastic leukaemia.

PubMed

Edwin, Claire; Dean, Joanne; Bonnett, Laura; Phillips, Kate; Keenan, Russell

2016-10-01

Composition of tumour immune cell infiltrates correlates with response to treatment and overall survival (OS) in several cancer settings. We retrospectively examined immune cells present in diagnostic bone marrow aspirates from paediatric patients with B-cell acute lymphoblastic leukaemia. Our analysis identified a sub-group (∼30% of patients) with >2.37% CD20 and >6.05% CD7 expression, which had 100% OS, and a sub-group (∼30% of patients) with ≤2.37% CD20 and ≤6.05% CD7 expression at increased risk of treatment failure (66.7% OS, P < 0.05). Immune cell infiltrate at diagnosis may predict treatment response and could provide a means to enhance immediate treatment risk stratification. © 2016 The Authors. Pediatric Blood & Cancer, published by Wiley Periodicals, Inc.

T-cell-replete haploidentical stem cell transplantation is highly efficacious for relapsed and refractory childhood acute leukaemia.

PubMed

Kobayashi, S; Ito, M; Sano, H; Mochizuki, K; Akaihata, M; Waragai, T; Ohara, Y; Hosoya, M; Ohto, H; Kikuta, A

2014-10-01

Despite improvements in first-line therapies, the outcomes of relapsed or refractory childhood acute leukaemia that has not achieved complete remission after relapse, has relapsed after stem cell transplantation (SCT), has primary induction failure and has relapsed with a very unfavourable cytogenetic risk profile, are dismal. We evaluated the feasibility and efficacy of T-cell-replete haploidentical peripheral blood stem cell transplantation (haplo-SCT) with low-dose anti-human thymocyte immunoglobulin (ATG), tacrolimus, methotrexate and prednisolone (PSL) in 14 paediatric patients with high-risk childhood acute leukaemia. All patients achieved complete engraftment. The median time to reaching an absolute neutrophil count of more than 0.5 × 10(9) L(-1) was 14 days. Acute graft-vs-host disease (aGVHD) of grades II-IV and III-IV developed in 10 (71%) and 2 (14%) patients, respectively. Treatment-related mortality and relapse occurred in one (7%) patient and six (43%) patients, respectively. Eleven patients were alive and seven of them were disease-free with a median follow-up of 36 months (range: 30-159 months). The probability of event-free survival after 2 years was 50%. These findings indicate that T-cell-replete haplo-SCT, with low-dose ATG and PSL, provides sustained remission with an acceptable risk of GVHD in paediatric patients with advanced haematologic malignancies. © 2014 The Authors. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.

Antagonism between granulocytic maturation and deacetylase inhibitor-induced apoptosis in acute promyelocytic leukaemia cells.

PubMed

Hennig, D; Müller, S; Wichmann, C; Drube, S; Pietschmann, K; Pelzl, L; Grez, M; Bug, G; Heinzel, T; Krämer, O H

2015-01-20

Transcriptional repression is a key mechanism driving leukaemogenesis. In acute promyelocytic leukaemia (APL), the fusion protein promyelocytic leukaemia-retinoic acid receptor-α fusion (PML-RARα) recruits transcriptional repressors to myeloid differentiation genes. All-trans-retinoic acid (ATRA) induces the proteasomal degradation of PML-RARα and granulocytic differentiation. Histone deacetylases (HDACs) fall into four classes (I-IV) and contribute to the transcription block caused by PML-RARα. Immunoblot, flow cytometry, and May-Grünwald-Giemsa staining were used to analyze differentiation and induction of apoptosis. A PML-RARα- and ATRA-dependent differentiation programme induces granulocytic maturation associated with an accumulation of the myeloid transcription factor CCAAT/enhancer binding protein (C/EBP)ɛ and of the surface protein CD11b. While this process protects APL cells from inhibitors of class I HDAC activity, inhibition of all Zinc-dependent HDACs (classes I, II, and IV) with the pan-HDACi (histone deacetylase inhibitor(s)) LBH589 induces apoptosis of immature and differentiated APL cells. LBH589 can eliminate C/EBPɛ and the mitochondrial apoptosis regulator B-cell lymphoma (BCL)-xL in immature and differentiated NB4 cells. Thus, BCL-xL and C/EBPɛ are newly identified molecular markers for the efficacy of HDACi against APL cells. Our results could explain the therapeutic limitations occurring with ATRA and class I HDACi combinations. Pro-apoptotic effects caused by pan-HDAC inhibition are not blunted by ATRA-induced differentiation and may provide a clinically interesting alternative.

Donor-derived CD19-targeted T cell infusion induces minimal residual disease-negative remission in relapsed B-cell acute lymphoblastic leukaemia with no response to donor lymphocyte infusions after haploidentical haematopoietic stem cell transplantation.

PubMed

Chen, Yuhong; Cheng, Yifei; Suo, Pan; Yan, Chenhua; Wang, Yu; Chen, Yao; Han, Wei; Xu, Lanping; Zhang, Xiaohui; Liu, Kaiyan; Chang, Lungji; Xiao, Lei; Huang, Xiaojun

2017-11-01

Relapse is a common cause of failure in patients with B-cell acute lymphoblastic leukaemia (B-ALL) after haploidentical haematopoietic stem cell transplantation (haplo-HSCT), and non-responders to donor lymphoblastic infusion after HSCT have a very poor prognosis. Although donor-derived CD19-directed chimeric antigen receptor-modified (CAR) T cells can potentially cure leukaemia, their effectiveness and safety have not been confirmed in relapsed B-ALL cases after haplo-HSCT. Between January 2015 and January 2017, two and four patients each received one and two infusions of CAR T cells from haplo-HSCT donors. Five (83·33%) achieved minimal residual disease (MRD)-negative remission; one patient was discharged automatically without evaluation after developing severe thrombotic microangiopathies. Four of five responsive patients relapsed after 2-7 months, and one died of sepsis following MRD-negative remission after a second infusion. None of the other second infusion recipients achieved a second complete remission. Five patients (83·33%) experienced eight courses of grade 1-3 cytokine release syndrome; two were treated with tocilizumab. Two (33·3%) and one patient developed grade 2 and 3 acute graft-versus-host disease (aGVHD), respectively; the former was controlled with glucocorticoids. Donor-derived CAR T-cell infusion seems be effective and safe for relapsed B-ALL after haplo-HSCT, although larger clinical studies are needed. © 2017 John Wiley & Sons Ltd.

The downregulation of miR-3173 in B-cell acute lymphoblastic leukaemia promotes cell invasion via PTK2.

PubMed

Tian, Lijun; Cao, Junhua; Ji, Qiang; Zhang, Chuanling; Qian, Tong; Song, Xianchuan; Huang, Baoshan; Tian, Xinyi

2017-12-16

MicroRNAs are important regulators of the pathogenesis of B-cell acute lymphoblastic leukaemia (B-ALL). In this study, we identified miR-3173 and its predicted target gene PTK2 were correspondingly differentially expressed in B-ALL patients. In B-ALL cell lines, CCK-8 proliferation assay revealed that miR-3173 could inhibit the cell proliferation. Moreover, transwell assay revealed that miR-3173 could also inhibit cell migration and invasion in B-ALL cell lines. Luciferase assays revealed that miR-3173 directly bound to the 3'untranslated region of PTK2, and western blotting showed that miR-3173 suppressed the expression of PTK2 at the protein level. Generally, this study indicates that miR-3173 negatively regulates PTK2 and inhibits proliferation and invasion of B-ALL cell lines. Thus, miR-3173 may represent a potential therapeutic molecule for B-ALL intervention. Copyright © 2017 Elsevier Inc. All rights reserved.

CoCr wear particles generated from CoCr alloy metal-on-metal hip replacements, and cobalt ions stimulate apoptosis and expression of general toxicology-related genes in monocyte-like U937 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Posada, Olga M., E-mail: O.M.PosadaEstefan@leeds.ac.uk; Gilmour, Denise; Tate, Rothwelle J., E-mail: r.j.tate@strath.ac.uk

Cobalt-chromium (CoCr) particles in the nanometre size range and their concomitant release of Co and Cr ions into the patients' circulation are produced by wear at the articulating surfaces of metal-on-metal (MoM) implants. This process is associated with inflammation, bone loss and implant loosening and led to the withdrawal from the market of the DePuy ASR™ MoM hip replacements in 2010. Ions released from CoCr particles derived from a resurfacing implant in vitro and their subsequent cellular up-take were measured by ICP-MS. Moreover, the ability of such metal debris and Co ions to induce both apoptosis was evaluated with bothmore » FACS and immunoblotting. qRT-PCR was used to assess the effects on the expression of lymphotoxin alpha (LTA), BCL2-associated athanogene (BAG1), nitric oxide synthase 2 inducible (NOS2), FBJ murine osteosarcoma viral oncogene homolog (FOS), growth arrest and DNA-damage-inducible alpha (GADD45A). ICP-MS showed that the wear debris released significant (p < 0.05) amounts of Co and Cr ions into the culture medium, and significant (p < 0.05) cellular uptake of both ions. There was also an increase (p < 0.05) in apoptosis after a 48 h exposure to wear debris. Analysis of qRT-PCR results found significant up-regulation (p < 0.05) particularly of NOS2 and BAG1 in Co pre-treated cells which were subsequently exposed to Co ions + debris. Metal debris was more effective as an inducer of apoptosis and gene expression when cells had been pre-treated with Co ions. This suggests that if a patient receives sequential bilateral CoCr implants, the second implant may be more likely to produce adverse effects than the first one. - Highlights: • Effects of CoCr nanoparticles and Co ions on U937 cells were investigated. • Ions released from wear debris play an important role in cellular response, • Toxicity of Co ions could be related to NO metabolic processes and apoptosis. • CoCr particles were a more effective inducer of apoptosis after cell priming. • CoCr particles were a more effective inducer of gene expression after cell priming.« less

Role of Rab5 in the formation of macrophage-derived foam cell.

PubMed

Chan, Lokwern; Hong, Jin; Pan, Junjie; Li, Jian; Wen, Zhichao; Shi, Haiming; Ding, Jianping; Luo, Xinping

2017-09-12

Foam cells play a key role in the occurrence and pathogenesis of atherosclerosis. Its formation starts with the ingestion of oxidized low-density lipoprotein (oxLDL). The process is associated with Ras related protein in brain 5 (Rab5) which plays a critical role in regulating endocytosis and early endosomal trafficking. Base on this, we presumed that Rab5 might participate in the maturation of foam cell. The aim of this study is to investigate the effect of Rab5 on macrophage cholesterol during the evolvement of macrophage when induced by oxLDL to the formation of foam cell. Immunohistochemistry was performed to analyze the distribution of macrophages and Rab5 in atherosclerotic plaque. RNA inteference study and transfection of inactive mutant (GFP-Rab5-S34N) and active mutant (GFP-Rab5-Q79L) in U937-derived macrophage were utilized to investigate the impact of Rab5 on the process of macrophage cholesterol, which could be detected by oil red O staining, determination of intracellular lipid content, filipin staining, nile red staining and the costaining of early endosome antigen-1 (EEA-1) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylin dicarbocyanine (Dil)-labelled oxLDL (Dil-oxLDL). Rab5 was found abundantly localized in macrophage rich areas of human atherosclerotic lesions. On the foam cell study, the expression of Rab5 was increased after the incubation of oxLDL. The inteference study indicated the depletion of Rab5 led to the decreases of oil red O staining areas, total cholesterol and cholesterol esters in U937-derived marophages. Moreover, the fluorescence intensity of filipin and nile red staining were lower in GFP-Rab5-S34N as compared with GFP-Rab5-Q79L. The confocal study demonstrated less Dil-oxLDL was internalized in GFP-Rab5-S34N as compared with GFP-Rab5-Q79L; the result showed also the decrease in colocalization of internalized Dil-oxLDL and EEA-1 for GFP-Rab5-S34N as compared with GFP-Rab5-Q79L. Rab5 plays an important role in modulating the intracellular cholesterol of macrophages and consequently mediating the formation of foam cells.

Therapy targets in glioblastoma and cancer stem cells: lessons from haematopoietic neoplasms.

PubMed

Cruceru, Maria Linda; Neagu, Monica; Demoulin, Jean-Baptiste; Constantinescu, Stefan N

2013-10-01

Despite intense efforts to identify cancer-initiating cells in malignant brain tumours, markers linked to the function of these cells have only very recently begun to be uncovered. The notion of cancer stem cell gained prominence, several molecules and signalling pathways becoming relevant for diagnosis and treatment. Whether a substantial fraction or only a tiny minority of cells in a tumor can initiate and perpetuate cancer, is still debated. The paradigm of cancer-initiating stem cells has initially been developed with respect to blood cancers where chronic conditions such as myeloproliferative neoplasms are due to mutations acquired in a haematopoietic stem cell (HSC), which maintains the normal hierarchy to neoplastic haematopoiesis. In contrast, acute leukaemia transformation of such blood neoplasms appears to derive not only from HSCs but also from committed progenitors that cannot differentiate. This review will focus on putative novel therapy targets represented by markers described to define cancer stem/initiating cells in malignant gliomas, which have been called 'leukaemia of the brain', given their rapid migration and evolution. Parallels are drawn with other cancers, especially haematopoietic, given the similar rampant proliferation and treatment resistance of glioblastoma multiforme and secondary acute leukaemias. Genes associated with the malignant conditions and especially expressed in glioma cancer stem cells are intensively searched. Although many such molecules might only coincidentally be expressed in cancer-initiating cells, some may function in the oncogenic process, and those would be the prime candidates for diagnostic and targeted therapy. For the latter, combination therapies are likely to be envisaged, given the robust and plastic signalling networks supporting malignant proliferation. © 2013 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

TESTIN Induces Rapid Death and Suppresses Proliferation in Childhood B Acute Lymphoblastic Leukaemia Cells

PubMed Central

Weeks, Robert J.; Ludgate, Jackie L.; LeMée, Gwenn; Morison, Ian M.

2016-01-01

Background Childhood acute lymphoblastic leukaemia (ALL) is the most common malignancy in children. Despite high cure rates, side effects and late consequences of the intensive treatments are common. Unquestionably, the identification of new therapeutic targets will lead to safer, more effective treatments. We identified TES promoter methylation and transcriptional silencing as a very common molecular abnormality in childhood ALL, irrespective of molecular subtype. The aims of the present study were to demonstrate that TES promoter methylation is aberrant, to determine the effects of TES re-expression in ALL, and to determine if those effects are mediated via TP53 activity. Methods Normal fetal and adult tissue DNA was isolated and TES promoter methylation determined by Sequenom MassARRAY. Quantitative RT-PCR and immunoblot were used to confirm re-expression of TES in ALL cell lines after 5’-aza-2’-deoxycytidine (decitabine) exposure or transfection with TES expression plasmids. The effects of TES re-expression on ALL cells were investigated using standard cell proliferation, cell death and cell cycle assays. Results In this study, we confirm that the TES promoter is unmethylated in normal adult and fetal tissues. We report that decitabine treatment of ALL cell lines results in demethylation of the TES promoter and attendant expression of TES mRNA. Re-expression of TESTIN protein in ALL cells using expression plasmid transfection results in rapid cell death or cell cycle arrest independent of TP53 activity. Conclusions These results suggest that TES is aberrantly methylated in ALL and that re-expression of TESTIN has anti-leukaemia effects which point to novel therapeutic opportunities for childhood ALL. PMID:26985820