bluuebunny/crossref_metadata_2025_split huggingface dataset:
Granulocyte-macrophage colony-stimulating factor stimulation results in phosphorylation of cAMP response element-binding protein through activation of pp90RSK
Authors: Kwon Evelyn M. , Raines Maribeth A. , Blenis John , Sakamoto Kathleen M. 
Published: October 2019

AbstractGranulocyte-macrophage colony-stimulating factor (GM-CSF) activates several kinases and transcription factors through interaction with a heterodimeric receptor complex. We previously demonstrated that phosphorylation of the cyclic adenosine monophosphate (cAMP) response element-binding protein, CREB, occurs through a protein kinase A-independent pathway and is required for GM-CSF–induced transcriptional activation of the immediate early gene, early growth response-1 (egr-1). Recent reports indicate that receptor tyrosine kinases can induce CREB phosphorylation through activation of pp90RSK. We performed immune complex kinase assays in the human myeloid leukemic cell line, TF-1, which revealed that GM-CSF induced pp90RSK activation and phosphorylation of CREB within 5 minutes of stimulation. Transfection with the kinase-defective pp90RSK expression plasmid demonstrated a statistically significant decrease in transcriptional activation of a −116 CAT/egr-1 promoter construct in response to GM-CSF. Furthermore, activation of pp90RSK, CREB and egr-1in GM-CSF–treated cells was inhibited by the presence of the inhibitor, PD98059. In this study, we report that GM-CSF induces CREB phosphorylation and egr-1 transcription by activating pp90RSK through an MEK-dependent signaling pathway.
Induction of apoptosis by extracellular ubiquitin in human hematopoietic cells: possible involvement of STAT3 degradation by proteasome pathway in interleukin 6-dependent hematopoietic cells
Authors: Daino Hanako , Matsumura Itaru , Takada Koji , Odajima Junko , Tanaka Hirokazu , Ueda Shuji , Shibayama Hirohiko , Ikeda Hirokazu , Hibi Masahiko , Machii Takashi , Hirano Toshio , Kanakura Yuzuru 
Published: October 2019

AbstractThe ubiquitin–proteasome pathway is responsible for selective degradation of short-lived cellular proteins and is critical for the regulation of many cellular processes. We previously showed that ubiquitin (Ub) secreted from hairy cell leukemia cells had inhibitory effects on clonogenic growth of normal hematopoietic progenitor cells. In this study, we examined the effects of exogenous Ub on the growth and survival of a series of human hematopoietic cells, including myeloid cell lines (HL-60 and U937), a B-cell line (Daudi), and T-cell lines (KT-3, MT-4, YTC-3, and MOLT-4). Exogenous Ub inhibited the growth of various hematopoietic cell lines tested, especially of KT-3 and HL-60 cells. The growth-suppressive effects of Ub on KT-3 and HL-60 cells were almost completely abrogated by the proteasome inhibitor PSI or MG132, suggesting the involvement of the proteasome pathway in this process. Furthermore, exogenous Ub evoked severe apoptosis of KT-3 and HL-60 cells through the activation of caspase-3. In interleukin-6 (IL-6)-dependent KT-3 cells, STAT3 was found to be conjugated by exogenous biotinylated Ub and to be degraded in a proteasome-dependent manner, whereas expression levels of STAT1, STAT5, or mitogen-activated protein kinase were not affected. Moreover, IL-6-induced the up-regulation of Bcl-2 and c-myc, and JunB was impaired in Ub-treated KT-3 cells, suggesting that the anti-apoptotic and mitogenic effects of IL-6 were disrupted by Ub. These results suggest that extracellular Ub was incorporated into hematopoietic cells and mediated their growth suppression and apoptosis through proteasome-dependent degradation of selective cellular proteins such as STAT3.
Isolation and characterization of an acute promyelocytic leukemia cell line selectively resistant to the novel antileukemic and apoptogenic retinoid 6-[3-adamantyl-4-hydroxyphenyl]-2-naphthalene carboxylic acid
Authors: Ponzanelli Isabella , Giannı̀ Maurizio , Giavazzi Raffaella , Garofalo Angela , Nicoletti Ines , Reichert Uwe , Erba Eugenio , Rambaldi Alessandro , Terao Mineko , Garattini Enrico 
Published: October 2019

Abstract
6-[3-adamantyl-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) is a novel compound that represents the prototype of a new class of synthetic retinoids with apoptogenic properties in acute promyelocytic leukemia (APL) and other types of leukemia. In this article, using SCID mice xenografted with APL-derived NB4 cells, we demonstrate that CD437 has significant antileukemic activity in vivo. In addition, we report on the isolation and characterization of an APL cell line (NB4.437r) resistant to CD437. The cell line retains expression of PML-RAR and is approximately 33-fold more resistant than the parental counterpart to the apoptogenic effects of the retinoid. Resistance is relatively specific to CD437 and structural congeners because the NB4.437r cell line is still sensitive to various types of apoptogenic compounds. The CD437-resistant cell line maintains sensitivity to the antiproliferative and apoptotic action of all-trans-retinoic acid, AM580, and fenretinide, though it shows partial resistance to the cytodifferentiating effects of the first 2 compounds. Resistance to CD437 lays upstream of the CD437-induced release of cytochrome c from the mitochondria and the activation of caspase-3, -7, -8, and -9. Furthermore, NB4.437r cells are deficient in the CD437-dependent activation of nuclear NFkb and AP1-binding activities and in the phosphorylation of the protein kinase Akt. In the case of AP1, deficient assembly of the complex is not caused by the lack of activation of the Jun N-terminal kinase (JNK) family of kinases. The novel cell line will be useful in the elucidation of the molecular mechanisms underlying the apoptogenic action of CD437 and structurally related retinoids.
Many multipotential gene-marked progenitor or stem cell clones contribute to hematopoiesis in nonhuman primates
Authors: Kim Hyeoung Joon , Tisdale John F. , Wu Tong , Takatoku Masaaki , Sellers Stephanie E. , Zickler Philipp , Metzger Mark E. , Agricola Brian A. , Malley James D. , Kato Ikunoshin , Donahue Robert E. , Brown Kevin E. , Dunbar Cynthia E. 
Published: October 2019

Abstract
Retroviral insertion site analysis was used to track the contribution of retrovirally transduced primitive progenitors to hematopoiesis after autologous transplantation in the rhesus macaque model. CD34-enriched mobilized peripheral blood cells were transduced with retroviral marking vectors containing the neo gene and were reinfused after total body irradiation. High-level gene transfer efficiency allowed insertion site analysis of individual myeloid and erythroid colony-forming units (CFU) and of highly purified B- and T-lymphoid populations in 2 animals. At multiple time points up to 1 year after transplantation, retroviral insertion sites were identified by performing inverse polymerase chain reaction and sequencing vector-containing CFU or more than 99% pure T- and B-cell populations. Forty-eight unique insertion sequences were detected in the first animal and also in the second animal, and multiple clones contributed to hematopoiesis at 2 or more time points. Multipotential clones contributing to myeloid and lymphoid lineages were identified. These results support the concept that hematopoiesis in large animals is polyclonal and that individual multipotential stem or progenitor cells can contribute to hematopoiesis for prolonged periods. Gene transfer to long-lived, multipotent clones is shown and is encouraging for human gene therapy applications.
Heparin-induced thrombocytopenia: new evidence for the dynamic binding of purified anti-PF4–heparin antibodies to platelets and the resultant platelet activation
Authors: Newman Peter M. , Chong Beng H. 
Published: October 2019

Abstract
Immune heparin-induced thrombocytopenia (HIT) is associated with antibodies directed against a complex of platelet factor 4 (PF4) and heparin. We were able to affinity purify anti-PF4–heparin IgG (HIT IgG) from the plasma of 2 patients with HIT. Under conditions that were more physiological and sensitive than those in previous studies, we observed that this HIT IgG caused platelet aggregation on the addition of heparin. Platelets activated with HIT IgG increased their release and surface expression of PF4. We quantitated, for the first time, the binding of affinity-purified HIT iodine 125–IgG to platelets as they activated in a plasma milieu. Binding of the HIT IgG was dependent on heparin and required some degree of platelet activation. Blocking the platelet FcγRII with the monoclonal antibody IV.3 did not prevent HIT IgG binding to activated platelets. We concluded that anti-PF4–heparin IgG is the component in these HIT plasmas that induces platelet aggregation. The Fab region of HIT IgG binds to PF4–heparin on the surface of activated platelets. We propose that only then does the Fc portion of the bound IgG further activate the same or adjacent platelets through the Fc receptor. Our data support a dynamic model of platelet activation in which released PF4 enhances further antibody binding and more release.
Human endothelial cells express CCR2 and respond to MCP-1: direct role of MCP-1 in angiogenesis and tumor progression
Authors: Salcedo Rosalba , Ponce Maria Lourdes , Young Howard A. , Wasserman Ken , Ward Jerrold M. , Kleinman Hynda K. , Oppenheim Joost J. , Murphy William J. 
Published: October 2019

AbstractAlthough several CXC chemokines have been shown to induce angiogenesis and play roles in tumor growth, to date, no member of the CC chemokine family has been reported to play a direct role in angiogenesis. Here we report that the CC chemokine, monocyte chemotactic protein 1 (MCP-1), induced chemotaxis of human endothelial cells at nanomolar concentrations. This chemotactic response was inhibited by a monoclonal antibody to MCP-1. MCP-1 also induced the formation of blood vessels in vivo as assessed by the chick chorioallantoic membrane and the matrigel plug assays. As expected, the angiogenic response induced by MCP-1 was accompanied by an inflammatory response. With the use of a rat aortic sprouting assay in the absence of leukocytic infiltrates, we ruled out the possibility that the angiogenic effect of MCP-1 depended on leukocyte products. Moreover, the direct effect of MCP-1 on angiogenesis was consistent with the expression of CCR2, the receptor for MCP-1, on endothelial cells. Assessment of supernatant from a human breast carcinoma cell line demonstrated the production of MCP-1. Treatment of immunodeficient mice bearing human breast carcinoma cells with a neutralizing antibody to MCP-1 resulted in significant increases in survival and inhibition of the growth of lung micrometastases. Taken together, our data indicate that MCP-1 can act as a direct mediator of angiogenesis. As a chemokine that is abundantly produced by some tumors, it can also directly contribute to tumor progression. Therefore, therapy employing antagonists of MCP-1 in combination with other inhibitors of angiogenesis may achieve more comprehensive inhibition of tumor growth.
Expression of Kell blood group protein in nonerythroid tissues
Authors: Russo David , Wu Xu , Redman Colvin M. , Lee Soohee 
Published: October 2019

AbstractThe Kell blood group protein is a zinc endopeptidase that yields endothelin-3, a potent bioactive peptide, by cleavage of big endothelin-3, a larger intermediate precursor. On red cells, Kell protein is linked by a single disulfide bond to XK, a protein that traverses the membrane 10 times and whose absence, as occurs in the McLeod phenotype, is associated with a set of clinical symptoms that include nerve and muscle disorders and red cell acanthocytosis. Previous studies indicated that Kell is primarily expressed in erythroid tissues, whereas XK has a wider tissue distribution. The tissue distribution of Kell protein has been further investigated by Northern blot analysis, PCR-screening of tissue complementary DNAs (cDNAs), and Western immunoblots. Screening of an RNA dot-blot panel confirmed that Kell is primarily expressed in erythroid tissues but is also expressed in a near equal amount in testis, with weaker expression in a large number of other tissues. PCR-screening of cDNAs from different tissues and DNA sequencing of the products gave similar results. In 2 of the nonerythroid tissues tested, testis and skeletal muscle, Kell protein was detected by Western immunoblotting. In skeletal muscle, isolation of XK with a specific antibody coisolated Kell protein. These studies demonstrate that Kell is expressed in both erythroid and nonerythroid tissues and is associated with XK.
Risk for subsequent venous thromboembolic complications in carriers of the prothrombin or the factor V gene mutation with a first episode of deep-vein thrombosis
Authors: Simioni Paolo , Prandoni Paolo , Lensing Anthonie W. A. , Manfrin Davide , Tormene Daniela , Gavasso Sabrina , Girolami Bruno , Sardella Corrado , Prins Martin , Girolami Antonio 
Published: October 2019

Abstract
Carriers of a mutation in the prothrombin (clotting factor II) or factor V gene have a 2- to 4-fold greater risk for venous thromboembolism than subjects without the mutations. Whether both mutations also predispose to recurrent venous thromboembolism is unclear. Outpatients who had a first episode of proven symptomatic deep-vein thrombosis and a long-term follow-up were studied. The outcome measure was the cumulative incidence of confirmed venous thromboembolic complications. Two hundred fifty-one patients were enrolled in the study. Mean duration of follow-up was 8.3 years. The prothrombin gene mutation was demonstrated in 27 patients (prevalence, 10.8%; 95% CI, 6.9 to 14.6), and the factor V gene mutation was demonstrated in 41 patients (prevalence, 16.3%; 95% CI, 11.8 to 20.9). The cumulative incidence of venous thromboembolic complications after 10 years was 61.3% (95% CI, 35.7 to 87.9), and the hazard ratio was 2.4 (95% CI, 1.3 to 4.7; P = .004) in patients with the prothrombin gene mutation); the cumulative incidence of venous thromboembolic complications after 10 years was 55.2% (95% CI, 36.4 to 74.0), and the hazard ratio was 2.4 (95% CI, 1.4 to 4.1;P = .001) in patients with the factor V gene mutation. In comparison, the cumulative incidence of venous thromboembolic complications after 10 years was 23.1% (95% CI, 16.2 to 30.1) in patients without the mutations. Prothrombin and factor V gene mutations occur frequently in patients with venous thrombosis and are associated with an increased risk for recurrent venous thromboembolic complications
Down-regulation of L-selectin expression in neutrophils by nonsteroidal anti-inflammatory drugs: role of intracellular ATP concentration
Authors: Gómez-Gaviro Maria Victoria , Domı́nguez-Jiménez Carmen , Carretero Jorge Moreno , Sabando Pedro , González-Alvaro Isidoro , Sánchez-Madrid Francisco , Dı́az-González Federico 
Published: October 2019

AbstractL-selectin is an adhesion molecule that plays an essential role in the early events of the inflammatory response. Our group has recently described that several nonsteroidal anti-inflammatory drugs (NSAIDs) are able to induce both in vivo and in vitro the shedding of L-selectin in neutrophils through an unknown mechanism. In this work, we have studied potential mechanisms involved in the shedding of L-selectin induced by NSAIDs. This effect of NSAIDs did not involve any detectable intracellular calcium flux. Pretreatment of neutrophils either with Ro 31-8220 and H7, 2 specific inhibitors of protein kinase C (PKC), or with inhibitors of protein tyrosine kinases such as tyrphostin A25 or herbimycin A did not prevent the NSAID-mediated L-selectin shedding. However, the KD-IX-73-4, an inhibitor of L-selectin proteolysis was able to block the effect of NSAIDs on L-selectin expression. Remarkably, NSAIDs caused a variable reduction in the neutrophil intracellular ATP concentration that highly correlated with the differential ability of NSAIDs to trigger L-selectin shedding (r = 0.8, P &lt; .01). In agreement with this finding, azide plus 2-deoxy-D-glucose, 2 metabolic blockers, also induced a rapid L-selectin shedding (65% ± 8%) without affecting the neutrophil viability, activation, or expression level of other surface molecules with soluble isoforms such as CD16 and CD59. These data indicate that the maintenance of L-selectin on the neutrophil surface requires energy consumption, which suggests that L-selectin is shed in neutrophils by default. Interestingly, NSAIDs seem to cause the shedding of L-selectin, at least in part, through the reduction of the intracellular ATP concentration.
Endogenous biosynthesis of thromboxane and prostacyclin in 2 distinct murine models of atherosclerosis
Authors: Praticò Domenico , Cyrus Tillmann , Li Hongwei , FitzGerald Garret A. 
Published: October 2019

Abstract
Thromboxane A2 is a potent vasoconstrictor and platelet agonist; prostacyclin is a potent platelet inhibitor and vasodilator. Altered biosynthesis of these eicosanoids is a feature of human hypercholesterolemia and atherosclerosis. This study examined whether in 2 murine models of atherosclerosis their levels are increased and correlated with the evolution of the disease. Urinary 2,3-dinor thromboxane B2 and 2,3-dinor-6-keto prostaglandin F1α, metabolites of thromboxane and prostacyclin, respectively, were assayed in apoliprotein E (apoE)-deficient mice on chow and low-density lipoprotein receptor (LDLR)-deficient mice on chow and a Western-type diet. Atherosclerosis lesion area was measured by en face method. Both eicosanoids increased in apoE-deficient mice on chow and in LDLR-deficient mice on a high-fat diet, but not in LDLR-deficient mice on chow by the end of the study. Aspirin suppressed ex vivo platelet aggregation, serum thromboxane B2, and 2,3-dinor thromboxane B2, and significantly reduced the excretion of 2,3-dinor-6-keto prostaglandin F1α in these animals. This study demonstrates that thromboxane as well as prostacyclin biosynthesis is increased in 2 murine models of atherogenesis and is secondary to increased in vivo platelet activation. Assessment of their generation in these models may afford the basis for future studies on the functional role of these eicosanoids in the evolution and progression of atherosclerosis.
5-lipoxygenase expression in dendritic cells generated from CD34+ hematopoietic progenitors and in lymphoid organs
Authors: Spanbroek Rainer , Hildner Markus , Steinhilber Dieter , Fusenig Norbert , Yoneda Kozo , Samuelsson Olof Rådmark, Bengt , Habenicht Andreas J.R. 
Published: October 2019

AbstractThe 5-lipoxygenase (5-LO) pathway in human CD34+ hematopoietic progenitor cells, which were induced to differentiate into dendritic cells (DCs) by cytokines in vitro and in DCs of lymphoid tissues in situ, was examined. Extracts prepared from HPCs contained low levels of 5-LO or 5-LO–activating protein. Granulocyte-macrophage colony-stimulating factor (GM-CSF) plus tumor necrosis factor–α (TNF-α) promoted DC differentiation and induced a strong rise in 5-LO and FLAP expression. Fluorescence-activated cell sorter (FACS) analyses identified a major DC population coexpressing human leukocyte antigen (HLA)-DR/CD80 and monocytic or Langerhans cell markers. Transforming growth factor–β1 (TGF-β–1), added to support DC maturation, strongly promoted the appearance of CD1a+/Lag+ Langerhans-type cells as well as mature CD83+ DCs. TGF-β–1 further increased 5-LO and FLAP expression, recruited additional cells into the 5-LO+DC population, and promoted production of 5-hydroxyeicosatetraenoic acid and leukotriene B4 in response to calcium (Ca++) ionophore A23187. These in vitro findings were corroborated by 5-LO expression in distinct DC phenotypes in vivo. Scattered 5-LO and FLAP in situ hybridization signals were recorded in cells of paracortical T-lymphocyte–rich areas and germinal centers (GCs) of lymph nodes (LNs) and tonsil and in cells of mucosae overlying the Waldeyer tonsillar ring. 5-LO protein localized to both CD1a+ immature DCs and to CD83+ mature interdigitating DCs of T-lymphocyte–rich areas of LNs and tonsil. As DCs have the unique ability to initiate naive lymphocyte activation, our data support the hypothesis that leukotrienes act at proximal steps of adaptive immune responses.
The aberrant fusion proteins PML-RARα and PLZF-RARα contribute to the overexpression of cyclin A1 in acute promyelocytic leukemia
Authors: Müller Carsten , Yang Rong , Park Dorothy J. , Serve Hubert , Berdel Wolfgang E. , Koeffler H. Phillip 
Published: October 2019

AbstractCyclin A1 is a newly discovered cyclin that is overexpressed in certain myeloid leukemias. Previously, the authors found that the frequency of cyclin A1 overexpression is especially high in acute promyelocytic leukemia (APL). In this study, the authors investigated the mechanism of cyclin A1 overexpression in APL cells and showed that the APL-associated aberrant fusion proteins (PML–retinoic acid receptor alpha [PML-RARα] or PLZF-RARα) caused the increased levels of cyclin A1 in these cells. The ectopic expression of either PML-RARα or PLZF-RARα in U937 cells, a non-APL myeloid cell line, led to a dramatic increase of cyclin A1 messenger RNA and protein. This elevation of cyclin A1 was reversed by treatment with all-trans retinoic acid (ATRA) in cells expressing PML-RARα but not PLZF-RARα. ATRA also greatly reduced the high levels of cyclin A1 in the APL cell lines NB4 and UF-1. No effect of ATRA on cyclin A1 levels was found in the ATRA-resistant NB4-R2 cells. Further studies using ligands selective for various retinoic acid receptors suggested that cyclin A1 expression is negatively regulated by activated RARα. Reporter assays showed that PML-RARα led to activation of the cyclin A1 promoter. Addition of ATRA inhibited PML-RARα–induced cyclin A1 promoter activity. Taken together, our data suggest that PML-RARα and PLZF-RARα cause the high-level expression of cyclin A1 seen in acute promyelocytic leukemia.
Evaluation of Apaf-1 and procaspases-2, -3, -7, -8, and -9 as potential prognostic markers in acute leukemia
Authors: Svingen Phyllis A. , Karp Judith E. , Krajewski Stan , Mesner Peter W. , Gore Steven D. , Burke Philip J. , Reed John C. , Lazebnik Yuri A. , Kaufmann Scott H. 
Published: October 2019

Abstract
Recent studies have suggested that variations in levels of caspases, a family of intracellular cysteine proteases, can profoundly affect the ability of cells to undergo apoptosis. In this study, immunoblotting was used to examine levels of apoptotic protease activating factor-1 (Apaf-1) and procaspases-2, -3, -7, -8, and -9 in bone marrow samples (at least 80% leukemia) harvested before chemotherapy from adults with newly diagnosed acute myelogenous leukemia (AML, 42 patients) and acute lymphocytic leukemia (ALL, 18 patients). Levels of each of these polypeptides varied over a more than 10-fold range between specimens. In AML samples, expression of procaspase-2 correlated with levels of Apaf-1 (Rs = 0.52, P &lt; .02), procaspase-3 (Rs = 0.56,P &lt; .006) and procaspase-8 (Rs = 0.64, P &lt; .002). In ALL samples, expression of procaspases-7 and -9 was highly correlated (Rs = 0.90,P &lt; .003). Levels of these polypeptides did not correlate with prognostic factors or response to induction chemotherapy. In further studies, 16 paired samples (13 AML, 3 ALL), the first harvested before induction therapy and the second harvested at the time of leukemia regrowth, were also examined. There were no systematic alterations in levels of Apaf-1 or procaspases at relapse compared with diagnosis. These results indicate that levels of initiator caspases vary widely among different leukemia specimens but cast doubt on the hypothesis that this variation is a major determinant of drug sensitivity for acute leukemia in the clinical setting.