bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preliminary Results Concerning the Prognosis Value of Vascular Endothelial Growth Factor (VEGF) in Chronic Myeloid Leukemia Patients Treated with Imatinib Mesylate.
Authors: Legros Laurence , Huault Sebastien , Mahon Francois-Xavier , Hueber Anne-Odile , Touitou Irit , Cassuto Jill-Patrice , Guilhot Joelle , Peudhomme Claude 
Published: October 2019

Abstract
Increased angiogenesis in bone marrow (BM) is one of the characteristics of chronic myeloid leukemia (CML), a clonal myeloproliferative disorder which expresses a chimeric Bcr/Abl protein. The therapeutic strategy in CML has been totally modified with the development of Imatinib Mesylate (STI571), a specific inhibitor of Bcr/Abl tyrosine kinase activity. Previously, we studied the effect of Imatinib on the Vascular Endothelial Growth Factor (VEGF), one of the most potent regulators of angiogenesis (1). Thus, we demonstrated, for the first time, the decrease in VEGF production in CML patients treated with Imatinib. It pointed out the potential prognostic value of determining the VEGF plasma level of patients in order to follow the evolution of this hematologic malignancy. Actually, we showed that low plasma VEGF levels could be one of the characteristics of complete cytogenetic remission.
However, investigations with a larger number of patients were necessary to evaluate the potential of VEGF levels in the monitoring of CML patients treated with Imatinib. So, we analyzed VEGF plasma level in patients treated in the SPIRIT, the CML French Group phase III, multicenter, open-label, prospective trial. Patients are randomized between the 3 experimental arms [IM 400mg daily in combination with Peg-IFN-α2a (Peg-IFNα2a, 90 μg weekly) or with Ara-C (20 mg/m2/day, days 15–28 of 28-day cycles) or IM 600mg daily] and the reference arm, IM 400mg daily. The Endpoint are overall survival (primary), rate and duration of hematologic, cytogenetic and molecular responses and tolerability. This VEGF evaluation is based on a cohort of 110 pts [median age 51 yrs (19–81); Sokal distribution : 30% of pts low, 37% intermediate, and 33% high]. Males predominated (62%) and percentage of patients enrolled in IM 400mg, IM 600mg, IM 400 with Ara-C and IM 400mg with Peg-IFN arm is respectively 28%, 28%, 24% and 30%. At diagnosis, the median of VEGF plasma level is 945 pg/ml (range: 42.3–4001.5). After 3 months of treatment, the median of VEGF level decreases significantly (p<0.05) to 116.4 pg/ml (range: 6.7–2780). After 6, 9, 12 months of treatment, the median of VEGF level was stabilized at respectively 104 pg/ml (range: 17.9–2244.9), 88.3 pg/ml (range: 21.2–907.4), 99 pg/ml (range: 22.1–689,2).
To determine prognosis value of VEGF we correlated the results with the cytogenetic and molecular response.
Pharmacological Blockade of NF-kB Targets Both Imatinib-Sensitive or -Resistant Chronic Myeloid Leukemia Cells for Cell Death.
Authors: Imbert Véronique , Lounnas Nadia , Frelin Catherine , Gonthier Nadège , Griessinger Emmanuel , Sirvent Nicolas , Hummelberger Michael , Cassuto Jil-Patrice , Mahon François-Xavier , Michiels Jean-François , Rousselot Philippe , Dreano Michel , Peyron Jean-François 
Published: October 2019

Abstract
The Bcr-Abl inhibitor imatinib is now the first line therapy for all newly diagnosed CML patients in chronic phase. Nevertheless resistance to the drug emerges as CML progresses to an acute deadly phase. Additional cellular targets should thus be identified to develop alternative therapeutic strategies. The transcription factor NF-kB is a pro-survival factor, found abnormally active in numerous hematologic malignancies. In the present study we show that the constitutive and abnormal activation of NF-kB in Bcr-Abl transformed BaF3 cells and in the LAMA84 CML line could be downregulated after inhibition of Bcr-Abl. Pharmacological blockade of NF-kB by the IKK2 inhibitor AS602868 (Serono International S.A.) prevented proliferation of BaF3/Bcr-Abl, LAMA84 and primary CML cells. Importantly, AS602868 led to apoptosis of an imatinib resistant variant of LAMA84 and of BaF3 clones expressing mutated form of Bcr-Abl derived from imatinib resistant patients. Moreover, NF-kB inhibition affected proliferation and hematopoietic colony formation of primary imatinib resistant CML cells. Finally, the IKK2 inhibitor prolonged survival of mice intravenously injected with the imatinib resistant clone LAMA84-r. Our data strongly suggest that NF-kB mediates important survival functions in CML cells for bcr-abl and that targeting NF-kB with the IKK2 inhibitor AS602868 may represent a new promising therapeutic strategy for CML treatment.
Whole Chromosome Painting and Multiplex Fluorescence In Situ Hybridization in Detecting Complex Chromosomal Aberrations in Myelodysplastic Syndromes.
Authors: Li Jianyong , Xiao Bing , Chen Lijuan , Zhu Yu , Xu Wei , Qiu Hairong 
Published: October 2019

Abstract
Objective To explore the value of the technique of whole chromosome painting (WCP) and multiplex fluorescence in situ hybridization (M-FISH) in the detection of complex chromosomal aberrations (CCAs) of myelodysplastic syndromes (MDS).
Methods M-FISH was used in seven MDS patients with CCAs detected by R-banding technique to refine CCAs, and to identify cryptic translocations and characterization of marker chromosomes. Dual-color WCP procedures were further performed in 7 cases to confirm some rearrangements detected by M-FISH.
Results In all cases, M-FISH confirmed all results of R-banding.The composition and origin of 6 kinds of marker chromosomes, 9 kinds of chromosomes with additional material undetermined and 5 kinds of derivative chromosomes undefined by CC were defined after M-FISH analysis; 4 kinds of cryptic translocations overlooked by CC were found on derivative chromosomes and previously normal appearing chromosomes. In addition, M-FISH revealed some nonrandom aberrations: aberrations involving chromosome 17 (5/7) and -5/5q- (4/7) were the two most frequent aberrations. Fluorescence flaring is a main factor leading to misinterpretations. Some misclassified and missed chromosomal aberrations by M-FISH were corrected by WCP.
Conclusions M-FISH is a powerful molecular cytogenetic tool in clarification of CCAs. Complementary WCP helped us identify misclassified and missed chromosomal aberrations by M-FISH. CC in combination with molecular cytogenetic techniques M-FISH and WCP can unravel complex chromosomal aberrations more precisely.
Causes of Thromboembolism in Polycythemia Vera Patients.
Authors: Ambrus Julian L. , Ambrus Clara M. , Akhter Selina , Islam Abul B.M.A. , Islam Pierre T. 
Published: October 2019

Abstract
Our experience and review of the literature suggests that thromboembolism is a major cause of morbidity and death in polycythemia vera patients. Using methods developed by our group (Ambrus et al, Angiology 34 418–426, 1984) we determined membrane fluidity, deformability of red cell membranes. We found that compared to normal controls, red cell membranes in polycythemia vera patients were relatively stiff and the red cells less deformable when passed through microtubules. These abnormal red cell membranes also caused platelet aggregation. In the circulation of polycythemia vera patients we also found increased platelet aggregates using the detection method of Wu et al (Wu et. al, Lancet2: 924–926 1974, Wu et. al, Thromb. Res.7:917–924, 1975). Other factors in the thromboembolic complications included
increased hematocrit hyperviscosity syndrome increased thromboxane A2 content of platelets increased tendency to disseminated intravascular coagulation (DIC) (factors involved were also investigated).
Red cell membrane fluidity and platelet aggregation may be points of therapeutic attention to prevent thromboembolic complications. Suggestions of approaches to this problem by future research will be discussed.
Mutation JAK2 V617F in Patients with Myeloproliferative Disorders and Technical Aspects of Its Detection.
Authors: Pekova Sona , Hoffmann Rudolf , Jindra Pavel , Novakova Ludmila , Kozak Tomas , Vozobulova Vera , Schutzova Miroslava , Balasz Jozef , Tomsikova Lucie , Prucha Miroslav 
Published: October 2019

Abstract
Myeloproliferative disorders (MPD) are a heterogeneous group of diseases that involve chronic myeloid leukemia (CML), polycythemia vera (PV), essential trombocythemia (ET), chronic idiopatic myelofibrosis (IMF), hypereosinophilic syndrome and chronic neutrophilic leukemia. Recently, it has been found that in Ph-negative MPD, acquired somatic mutation in JAK2 gene can be identified, causing substitution of valine for phenylalanine at aminoacid position 617 (V617F). Experimental evidence indicates that JAK2 V617F might cause erythropoietin-independence of erythroid colonies and receptor hypersensitivity, thus be implicated in the pathogenesis of PV.
The incidence of V617 in PV is high, reaching 96% of cases; in ET or IMF, the mutation is less frequent. Nevertheless, the percentage of JAK2 V617F-positive patients differs greatly among studies, depending on the detection technique used. Sequencing analysis, as one of the options, can underrate the number of positive cases, as its sensitivity in authentic samples with varying proportion of mutant granulocytes is unsatisfactory. The nucleotide context of the V617F site is complicated (direct repeat TGTG/TT), and thus prone to sequencing artifacts.
For specific and sensitive detection of V617F mutation in JAK2 gene, we have developed a novel allelic discrimination assay, based on the usage of Real-Time PCR technology and LNA-modified fluorescently labeled probes (Locked Nucleic Acids). This technology is distinguished by 100% discrimination efficiency, and sensitivity detection rate reaching 10% of mutant granulocytes in an authentic sample. LNA-modified probes are extremely powerful tool for precise genotyping, since they are short (12-mers), and due to the interspersed LNA nucleotides, melting temperature (Tm) of the probe/target hybrid is high. Hence, the LNA-based genotyping technology combines the desired features of high sensitivity and absolute specificity.
Herein, we present an analysis of JAK2 V617F detection in our group of 157 consecutive patients with the diagnosis of MPD or suspected MPD. Using our novel LNA-based Real-Time PCR genotyping technique, we were able to identify varying proportions of the mutant JAK2 allele in 87 cases (55.4%); in the remaining 70 patients the mutation was not detected.
The LNA-based Real-Time PCR technique is extremely precise and efficient in identifying even subtle proportion of JAK2 V617F mutant granulocytes, which in cases of diagnostic uncertainties on the origin of the polycythemia might be of great importance.
The Jak2-Inhibitor AG409 Affects Survival of BFU-E and CFU-GM of Myeloproliferative Disorder Cells Carrying the JAK2 V617F Mutation.
Authors: Duek Adrian , Lichman Ina , Shtalrid Mordejai , Berrebi Alain 
Published: October 2019

Abstract
In the last few years, point mutation of the Janus Kinase 2 (JAK2) gene (V617F) was found in the majority of patient with Polycythemia Vera and two related diseases ET and MMM. This mutation initiates constitutive activation of JAK2 transduction gene, inducing growth factor- independent hemopoiesis and plays a dominant role in origin of myeloproliferative disorder. Inactivation of this mutated gene may restore the normal hemopoiesis. Based on the evidence that the inhibition of the Jak-Stat axis by AG490 induced apoptosis in leukemic compared with normal cell, we attempt to analyzed the AG490 effect on the survival of MPD cells carrying JAK2 mutation in cultures.
Peripheral blood (PB) samples were collected from 49 MPD patients (PV n=31, ET n=14, MMM n=4) at the time of diagnosis or during the follow up. The JAK2-V617F mutation tested by an allele-specific, semi-quantitative PCR was detected in 35 patients. MNPBC’s from four patients homozygous for the JAK2 mutation and from two normal volunteers were cultured in methylcellulose with 50 ng/ml SCF, 10ng/ml GM-CSF, 10ng/ml IL-3 and 3U/ml EPO, and in the same medium without growth factors. On the sixth day, 50 micromole of AG490 were added to the cultures and dishes with no addition of AG490 were kept for control. Colonies were counted on 6th day and on 14th day, and we checked the growth patterns on 14th day.
Spontaneous colonies without growth factors were found only in the four MPD patients. Although, the number of the colonies was not significantly decreased after the addition of the AG490 inhibitor, we observed an obvious change in the normal growth pattern. The appearance of the colonies became darker reflecting an apoptotic process and death.
Such a phenomenon was not seen in normal controls or in MPD cells without addition of the inhibitor. In conclusion our experiment clearly demonstrated preferential inhibition of MPD cells with JAK2 mutation by AG490, probably by induction of apoptosis. Our results suggest a therapeutic potential of inhibitors of JAK2 for the future.
LEF-1 Regulates C/EBP α Expression and Neutrophil Differentiation in Normal Myelopoiesis and Congenital Neutropenia by a β-Catenin Independent Mechanism.
Authors: Skokowa Julia , Uenalan Murat , Schambach Axel , Scherr Michaela , Eder Matthias , Zeidler Cornelia , Baum Christopher , Stanulla Martin , Cario Gunnar , Welte Karl 
Published: October 2019

Abstract
Lymphoid enhancer-binding factor 1 (LEF-1) belongs to the canonical Wnt signaling pathway acting in transcriptional complexes with β-catenin. LEF-1 can also act independent of β-catenin (i.e. in the TGF-β or Notch pathway). Additionally, recent studies described LEF-1 dominant negative isoform (dnLEF-1), which lack the β-catenin binding domain and functions as either a transcriptional repressor or activator. To date, analysis of the role of LEF-1 in hematopoiesis has been restricted to the lymphoid compartment.
Previously we described the crucial role of lymphoid enhancer-binding factor 1 (LEF-1) in granulopoiesis. We found that LEF-1 mediates proliferation, survival, and differentiation of granulocyte progenitor cells. Moreover, abrogated LEF-1 expression is one of the pathomechanism of severe congenital neutropenia CN (Skokowa et al., Nature Medicine, in press). Based on these findings, we aimed to characterize the molecular mechanisms of LEF-1 in the regulation of granulocytic differentiation. C/EBPα is well known as a key transcription factor in granulopoiesis and we found it to be a target gene directly regulated by LEF-1. A screen of the known 566 bp upstream promoter of C/EBPα gene revealed a putative LEF-1 binding site (− 559 bp to − 538 bp). We confirmed LEF-1 binding to C/EBPα promoter in nuclear extracts from CD34+ and CD33+ cells in the transcription factor binding NoShift and ChIP assays. Interestingly, LEF-1 binds to the C/EBPα promoter more efficiently in CD33+ myeloid progenitors than in CD34+ cells. The direct regulation of C/EBPα by LEF-1 was further confirmed in functional studies. We found that in line with down-regulation of LEF-1, expression of C/EBPα was also significantly reduced in CD33+ myeloid progenitors of CN patients. Moreover, LEF-1 rescue of these cells resulted in a marked up-regulation of C/EBPα mRNA expression and in vitro restoration of defective granulocytic differentiation. Remarkably, transduction of CN CD33+ cells with dnLEF-1 isoform, which lacks the ß-catenin-binding domain, resulted in up-regulation of C/EBPα to a similar degree as it was observed with full-length LEF-1. A direct regulatory link between LEF-1 and C/EBPα was additionally confirmed in LEF-1 inhibition experiments. C/EBPα expression was significantly down-regulated in CD34+ cells of healthy individuals, transduced with LEF-1 shRNA. Therefore, we propose that LEF-1 is a key regulator of myeloid differentiation acting in a β-catenin-independent manner, similar as it is known for LEF-1 regulation of T-lymphocyte development.
IL-6 Down-Regulates CD33 Expression in Primary Myeloma Cells as Well as Myeloma Cell Lines.
Authors: Shamsasenjan Karim , Abroun Saeid , Liu Shngqin , Amin Jakia , Islam Khademul , Otsuyama Ken-ichiro , Kawano Michio M. 
Published: October 2019

Abstract
Human primary myeloma cells show the marked heterogeneity of surface marker expression and morphology; possibly for myeloma cells lose the expression of PAX-5 and EBF, master genes of B cell lineage. As reported previously, we detected the expression of a myeloid marker, CD33, in the primary myeloma cells in about 10% out of 60 cases with overt myelomas as well as in 2 myeloma cell lines (Liu-01 and ILKM8 cells) by RT-PCR and flowcytometry using 4 different anti-CD33 antibodies. The expression of CD33 in these cells appeared to be well correlated to the monocytoid morphology with convoluted nuclei, and furthermore correlated to the increased expression of PU.1 and C/EBPα genes. Induction of CD33 expression was also found by the treatment with vitamin D3 in some primary myeloma cells as well as ILKM3 cell lines. This induction was not found in PAX-5(+) B cell lines (KUS and Raji cells). Interestingly, IL-6 down-regulated the expression of CD33 in Liu-01 and ILKM8 cell lines; if cultured with IL-6 (10 ng/ml) for 12 days, the expression of CD33 on Liu-01 cells completely disappeared. By IL-6 stimulation, the morphology of Liu-01 cells was also reversed to the morphology with round nuclei. Also, it is confirmed that IL-6 markedly suppressed the expression of PU.1 and C/EBPα genes in Liu-01 cells. Therefore, these data suggest that IL-6, a growth factor for myeloma cells, could reverse phenotypic conversion of non-B cell lineage such as CD33(+) myeloid/monocytoid cells to the B cell lineage.
Molecular Cytogenetic Study of Immunofluorescently Labeled Plasma Cells and Prognostic Significance of Clonal Chromosomal Aberrations in Multiple Myeloma.
Authors: Michalova Kyra , Zemanova Zuzana , Pavlistova Lenka , Tajtlova Jana , Spicka Ivan , Zounar Rene , Gregora Evzen , Smolikova Alena , Chrz Michal , Obernauerova Jarmila , Walterova Lenka 
Published: October 2019

Abstract
Finding of clonal chromosomal aberrations in plasma cells is considered as one of the most important and independent prognostic factor in patients with multiple myeloma (MM). The most frequent and reliable cytogenetic indicators are chromosome 13q deletions (intermediate or moderately adverse prognosis), and translocations involving the immunoglobulin heavy chain gene (IgH) at 14q32 region. IgH gene is involved in translocations with different partner genes and these rearrangements are related to a very poor prognosis. The only exception is translocation t(11;14)(q13;q32) which is often connected with longer overall survival and therefore considered to be a favorable prognostic factor. The aim of the study was to assess the frequency of the most important chromosomal aberrations in immunofluorescently labeled plasma cells of patients with MM by interphase fluorescence in situ hybridization (I-FISH), and to evaluate their prognostic significance.
During the last two years we examined 128 newly diagnosed patients with MM by conventional G-banding technique and by I-FISH. We focused on detection of aberrations of 13q, IgH gene rearrangements, and t(11;14)(q13;q32) translocation. I-FISH was done by locus-specific DNA probes (Abbott-Vysis, Des Plaines, Illinois, USA). Fifteen patients with complex karyotype were re-examined by multicolor FISH (mFISH, MetaSystems GmbH, Altlussheim, Germany). G-banding revealed abnormal karyotypes in 25% of patients, I-FISH detected chromosomal abberations in 82.8% cases. Abberations of chromosome 13 were found in plasma cells of 84 patients (65,6%), the incidence was: del(13)(q14) in 11%, monosomy 13 in 40%, combination of del(13)(q14)/monosomy 13 in 8%, and other aberrations of chromosome 13 in 7% of cases. Aberrations of IgH gene were proved in 82 patients (64%). t(11;14)(q13;q32) was seen in fourteen patients (11%) and other translocations affecting 14q32 region in 19 patients (15%). Besides translocations, different variations of total and/or partial deletions of IgH gene were detected in 28 cases (22%). In nine patients (7%) we found clones with translocation and deletion of 14q32 simultaneously, twelve patients (9%) had other IgH aberrations. Univariate statistical testing showed aberrations of 13q (p=0.042), and IgH gene rearrangments (translocations except t(11;14)(q13;q32) or deletions; p=0.007) to be associated with significantly shorter progression-free survival. The worst prognosis in our cohort was for 18 patients with combination of chromosome 13 anomalies together with rearrangements of IgH gene (p=0.049). Method of immunofluorescent labeling of plasma cells allows higher detection of chromosomal changes by I-FISH technique and therefore correct prognosis of the disease can be done.
Putative Substrates of AKT in Multiple Myeloma Cells.
Authors: Yew Lee Ping , Chen Chih-Hao , Chu Bo-Feng , Ho Yen-Peng , Hsu Jung-Hsin 
Published: October 2019

Abstract
The serine/threonine protein kinase AKT (also known as protein kinase B) is thought to be a key mediator of signal transduction processes. The AKT kinase is activated in myeloma tumor cells. Frequent AKT activation in situ in myeloma cells of patient bone marrow has been demonstrated. IL-6 is a known growth factor of myeloma cells. Recent evidence indicates that AKT plays a critical role in IL-6-dependent expansion of multiple myeloma clones. A method to identify serine kinase substrates has been described. In that method, an antibody specific for the phosphomotif generated by the kinase is used to isolate phosphorylated substrates by immunoprecipitation, and the isolated proteins are identified by tandem mass spectrometry of peptides. This method has been adopted in identifying putative substrates of AKT in mutiple myeloma cells. AF-10 cells of myeloma cell line were treated with IL-6 to activate AKT, and the putative AKT substrates were isolated by immunoprecipitation with PAS (phosphospecific Ser/Thr AKT substrate) antibody. The isolated proteins were identified by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. In Western blot probed with PAS antibody, intensities of putative AKT substrates increased with IL-6 treatment, but decreased when the cells were preincubated with wortmannin (a specific PI 3-kinase inhibitor) then treated with IL-6. Putative AKT substrates identified include: nonmuscle myosine-9, vimentin, and tubulin beta-2. All these proteins contain appropriate motifs of AKT substrates (R/KXRXXS/T, XXRXXS/T). Conformation studies and studies of the physiological significances of these putative substrates are undergoing. Recently, it has been reported that a novel isocoumarin derivative induces mitotic phase arrest and apoptosis of human mutiple myeloma cells by affecting tubulin assembly.