bluuebunny/crossref_metadata_2025_split huggingface dataset:
MicroRNA Signatures In B-Cell Lymphomas
Authors: Di Lisio Lorena , Sanchez-Beato Margarita , Gomez-Lopez Gonzalo , Rodriguez Maria E. E. , Montes-Moreno Santiago , Mollejo Manuela , Menarguez Javier , Martinez Miguel A. , Alves Javier , Pisano David G. , Piris Miguel A. , Martinez Nerea 
Published: October 2019

Abstract
Abstract 4155
Beyond the conventional criteria of lymphoma classification (integrated clinical, morphological, immunophenotypic, and molecular features) additional markers are still required for a more precise differential diagnosis and a better understanding of lymphoma pathogenesis.
MicroRNAs (miRNA) are non-coding small RNAs that play an important role in gene expression regulation, contributing to cell differentiation and tumorigenesis. Specifically, miRNAs have been already described to play a relevant role in B cell differentiation, and in some cases proposed to constitute lymphoma-type specific markers and possible therapeutic targets.
We explore the potential diagnostic application of miRNA expression in a large series of 147 cases including all B-cell non-Hodgkin lymphomas (NHL) major types and appropriate controls. As an example of a practical application, data were also used to identify miRNAs differentially expressed when comparing Burkitt Lymphoma (BL) and Diffuse Large B-Cell Lymphoma (DLBCL) in paraffin-embedded samples.
Each lymphoma type (BL, CLL, DLBCL, FL, MCL, MZL/MALT, NMZL and SMZL) was compared to the whole series of NHL by Significant Analysis of Microarray (SAM) method. The analysis identified a set of 128 characteristic miRNAs (FDR&lt;0.01 and Fold change &gt;1.5 log2). All lymphoma types were characterized by specific miRNA signatures, reflecting cell of origin and/or discrete oncogene alterations. Of interest is also the comparison with reactive lymphoid tissues, since it revealed a specific B-cell lymphoma miRNA profile, which includes a cluster of downregulated miRNAs, such as let7 family, miR-1 and miR-200 family.
Burkitt Lymphoma was also directly compared to DLBCL, and 43 miRNA selected by SAM analysis were studied in a new series of 28 BL and 43 DLBCL samples using quantitative RT-PCRIn this second step, the differential expression of a set of 19 miRNAs was confirmed between BL and DLBCL. (FDR &lt; 0.05 after t-test (limma)).
These findings expand the potential diagnostic markers in lymphoma diagnosis and provide useful information on lymphoma pathogenesis.

Disclosures:
No relevant conflicts of interest to declare.
Endogenous Oncogenic Nras Mutation Leads to Aberrant GM-CSF Signaling In Granulocytic/Monocytic Precursors In a Murine Model of Chronic Myelomonocytic Leukemia
Authors: Wang Jinyong , Liu Yangang , Li Zeyang , Du Juan , Ryu Myung-Jeom , Taylor Philip , Fleming Mark D. , Young Ken H , Pitot Henry , Zhang Jing 
Published: October 2019

Abstract
Abstract 4180
Oncogenic NRAS mutations are frequently identified in myeloid diseases involving monocyte lineage. However, its role in the genesis of these diseases remains elusive. We report a mouse bone marrow transplantation model harboring an oncogenic G12D mutation in the Nras locus. Approximately 95% of recipient mice develop a myeloproliferative disease resembling the myeloproliferative variant of chronic myelomonocytic leukemia (CMML), with a prolonged latency and acquisition of multiple genetic alterations, including uniparental disomy of oncogenic Nras allele. Based on single-cell profiling of phospho-proteins, a novel population of CMML cells is identified to display aberrant GM-CSF signaling in both the ERK1/2 and Stat5 pathways. This abnormal signaling is acquired during CMML development. Further study suggests that aberrant Ras/ERK signaling leads to expansion of granulocytic/monocytic precursors, which are highly responsive to GM-CSF. Hyperactivation of Stat5 in CMML cells is mainly through expansion of these precursors rather than upregulation of surface expression of GM-CSF receptor. Our results provide insights into the aberrant cytokine signaling in oncogenic Nras-associated myeloid diseases. Our mouse model will serve as a powerful system to identify and validate cooperating mutations of oncogenic Nras in myeloid leukemias as well as assess the therapeutic efficacy of molecular agents in treating these leukemias.

Disclosures:
No relevant conflicts of interest to declare.
A Large, Population Based Study of Sex Differences In the Risk of Recurrent Venous Thromboembolism
Authors: Kondal Dimple , Taglalakis Vicky , Moride Yola , Boivin Jean-François , Kahn Susan 
Published: October 2019

Abstract
Abstract 4204

Background.
Most reports of patient sex differences in the risk of recurrent VTE have been based on small or moderate sized cohorts of selected patients with VTE.

Objectives.
We used the administrative hospital discharge registry of Quebec, Canada to conduct a population-based retrospective cohort study to evaluate the effect of sex on rates of recurrent VTE.

Methods.
Using data from the province-wide hospital discharge database (Med-Echo) which systematically records information on all hospital admissions in the province of Quebec since 1967, we constructed a cohort of all individuals who had a first-time discharge diagnosis of deep vein thrombosis (DVT) or pulmonary embolism (PE) between January 1, 1996 and December 31, 2004 and no prior discharge diagnosis for DVT or PE back to 1983. Subjects were followed from the time of diagnosis until first VTE recurrence, death, or end of study (December 31, 2005). DVT and PE were defined based on the International Classification of Diseases, 9th edition, Clinical Modification.

Results.
The cohort comprised 55,314 patients (43% men and 57% women) with incident VTE. Mean age was 61.9 years (60.4 years (men) vs. 63.1 years (women); p=0.0001), and 33,535 (61%) had DVT alone, 14,574 (26%) had PE alone and 7,205 (13%) had both DVT and PE. During a mean follow-up of 3.9 years, 5,243 (9.5%) of patients developed recurrent VTE, which corresponded to an incidence rate of 2.4 events per 100 patient-years (95% confidence interval (CI), 2.3–2.5 per 100 patient-years). In survival analysis, men had significantly higher rate of recurrence than women (age- and comorbidity-adjusted hazard ratio = 1.14; 95% CI, 1.08–1.21), and at 5 years, the cumulative risk of recurrent VTE was 8.3% among men vs. 7.3% among women (p=0.0001). Mean age at the time of VTE recurrence in men vs. women was 61.1 years and 64.4 years, respectively (p=0.0001).

Conclusion.
Our study of over 55,000 patients hospitalized with VTE is the largest to date to report an effect of patient sex on risk of VTE recurrence, with men having about a 15% higher risk of recurrence than women. This provides further evidence that the difference in risk of VTE recurrence between men and women is significant and if confirmed by ongoing prospective management studies, patient sex should be considered in determining duration of anticoagulation treatment in patients with VTE.

Disclosures:
Taglalakis: Pfizer: Research Funding; Sanofi Aventis: Honoraria. Kahn:Sigvaris: Research Funding; sanofi-aventis: Advisory Board, Research Funding; Boehringer Ingelheim:.
MASL1 Induces Erythroid Differentiation In Human Erythropoietin-Dependent CD34+ Cells Involving Raf/MEK/ERK Signaling Pathway
Authors: Kumkhaek Chutima , Aerbajinai Wulin , Liu Wenli , Zhu Jianqiong , Uchida Naoya , Hsieh Matthew M , Tisdale John F , Rodgers Griffin P. 
Published: October 2019

Abstract
Abstract 4228
Human erythropoiesis is a dynamic complex multistep process that involves differentiation of early erythroid progenitors to enucleated red blood cells. Importantly, erythroid differentiation involves lineage-specific activation and restriction of gene expression. However, the mechanisms that play a role in erythropoiesis still remain incompletely understood. We previously demonstrated that erythropoietin-stimulated clone-1 (EP1), which is selectively expressed in normal human erythroid lineage cells shares 99.5% identity with the malignant fibrous histiocytoma amplified sequence 1(MFHAS1 or MASL1). MASL1 is an important oncogene that is highly expressed in malignant fibrous histiocytomas (MFH). MASL1 protein has several domains; ras, three leucine zipper, ATP/GTP-binding site and leucine-rich tandem repeat motif which are important structural or functional elements for interactions among proteins related to the cell cycle. However, the function of the MASL1 gene in erythropoiesis has not been studied. We hypothesized that MASL1 gene plays a role in the erythroid differentiation, and used a human liquid erythroid culture system to explore this concept. MASL1 mRNA and protein expression levels were significantly increased during the erythroid differentiation of CD34+ cells following EPO treatment. Conversely, small interfering RNA-mediated knock down of MASL1 in CD34+ cells resulted in a reduction of a double positive of transferrin receptor and glycophorin A (GPA) (14.1 ± 4.7%) when compared with mock (77.9 ± 4.4%) or control vector-transfected CD34+ cells (76.7 ± 8.8%) at day 14. May-Grunwald-Giemsa staining confirmed a phenotype of MASL1 knockdown CD34+ cells that most of cells were pro- or basophilic erythroblasts. Western blotting also showed a significant decrease in hemoglobin protein levels in MASL1 knockdown CD34+ cells. In addition, MASL1-knockdown in CD34+ cells demonstrated an interruption of Raf/MEK/ERK signaling pathway. Inhibition assay of SH3 domain of Son of Sevenless (SOS) which is an upstream adapter protein in EPO-induced erythroid differentiation, confirmed that a suppression of MASL1 reduced the phosphorylation of Raf/MEK/ERK kinases and delays erythroid differentiation of Epo-induced CD34+ cells. Taken together, our study provides novel insights into MASL1-regulated erythropoiesis through the Raf/MEK/ERK signaling pathway.

Disclosures:
No relevant conflicts of interest to declare.
A Simple Regimen to Correct Vitamin D Deficiency In Transfusion-Dependent Thalassemia with High-Dose Ergocalciferol
Authors: Lal Ashutosh , Micaily Ida , Foote Drucilla , Fung Ellen 
Published: October 2019

Abstract
Abstract 4261
Osteoporosis in thalassemia is extremely common and preventive approaches are required to avoid serious complications in adults. Vitamin D deficiency, which contributes to suboptimal bone mineralization, is frequently observed in thalassemia despite routine prescription for supplementation with 400–800 IU vitamin D per day. Screening for vitamin D status was conducted in 71 patients with thalassemia, of which 52 were transfusion-dependent and 19 were transfusion-independent (including 11 patients with hemoglobin H or H Constant Spring disease). Baseline assessment of plasma 25-OH vitamin D revealed 57 (80.3%) patients were either deficient (<20 ng/mL, 47.9%) or insufficient (20-30 ng/mL, 32.4%). Significantly more patients in the transfusion-independent group were deficient in vitamin D compared with transfusion-dependent group (78.9% versus 36.5%, p=0.003). The mean parathyroid hormone level in patients with 25-OH D <20 ng/mL was 35.4 ± 19.6 pg/mL compared to 28.2 ± 17.1 pg/mL in those with ≥20 ng/mL (p=NS). We studied the efficacy of supervised adminstration of high-dose (50,000 IU) oral ergocalciferol every 3 weeks during transfusion visits in 20 patients with transfusion-dependent thalassemia. The mean 25-OH D level increased from 14.0 to 22.9 ng/mL (p<0.001) over a four-month period. A single dose of ergocalciferol given every 3 weeks increased the plasma 25-OH D level by 2.2 ± 2.3 ng/mL. No patient developed toxic 25-OH D level (>80 ng/mL) during the course of the study. These results show that vitamin D deficiency remains widespread despite daily low-dose supplementation. Non-transfused patients are at even greater risk of vitamin D deficiency, which may reflect less attention to nutrition in this group compared to the transfusion-dependent patients. We have found that supervised high-dose oral ergocalciferol supplementation is simple, safe, non-invasive and predictable method to improve vitamin D status in thalassemia.

Disclosures:
No relevant conflicts of interest to declare.
Myocardial Fibrosis by Delayed Enhancement Cardiovascular Magnetic Resonance and HCV Infection In Thalassemia Major Patients
Authors: Pepe Alessia , Meloni Antonella , Borsellino Zelia , Dell'Amico Maria Chiara , Borgna-Pignatti Caterina , Maggio Aurelio , Positano Vincenzo , Cracolici Eliana , Lombardi Massimo , Capra Marcello 
Published: October 2019

Abstract
Abstract 4265

Introduction.
Delayed enhancement (DE) cardiac magnetic resonance (CMR) technique with intravenous administration of gadolinium (Gd) chelates contrast agents is the only validated non-invasive approach for detecting myocardial fibrosis (Mahrholdt H et al, Eur Heart J 2005). This technique has been confirmed safe in patients with hemoglobinopathies (Meloni A et al, Haematologica 2009). In thalassemia major (TM), myocardial fibrosis has been detected using the DE technique and a positive correlation with anti-HCV antibodies has been described (Pepe A et al, Heart 2009). However, HCV-induced cardiomyopathy is still controversial (Matsumori A et al. J Card Fail 2006). The aim of our study was to verify a possible correlation between myocardial fibrosis detected by DE CMR and chronic HCV infection in a large retrospective cohort of TM patients.

Methods.
We analysed 434 TM patients (233 males, mean age 31±9 years) consecutively enrolled in the MIOT (Myocardial Iron Overload in Thalassemia) network (Ramazzotti A et al, JMRI 2009). DE images were acquired from 10 to 18 minutes, after intravenous administration of Gadobutrol. DE was evaluated visually using a two-point scale (absent or present) and enhancement was considered present whenever it was visualized in two different views (Pepe A et al, Heart 2009). HCV-RNA tests were sensitive to detect more than 50 copies/ml.

Results.
Figure 1 represents the flow chart of the test results in the 434 TM patients. Ninety out of 434 TM patients (21%) were found to have myocardial fibrosis by DE CMR technique. Chronic hepatitis C (CHC) group was composed by HCV-RNA positive patients plus the patients with a previous diagnosis of CHC successfully treated by alpha-interferon for obtaining a sustained virological response (SVR). There was a significant correlation between the presence of myocardial fibrosis and CHC (P=0.026).

Conclusions.
Our finding supports the hypothesis that HCV infection can be involved in the pathogenesis of myocardial fibrosis in the multitransfused TM patients, who could therefore benefit from therapeutic interventions directed towards the eradication of HCV.

Disclosures:
No relevant conflicts of interest to declare.
Nuclear Factor of Activated T-Cells (NFAT1): Novel Target In T-Cell Acute Lymphocytic Leukemia (T-ALL)
Authors: Potoczak Alexander Douglas , Lesniewski Mathew , Havernik Peter , Pillai Esha , Weitzel R. Patrick , Greco Nicholas J , Forster Margaret , Laughlin Mary J. 
Published: October 2019

Abstract
Abstract 4327

Background:
The well-characterized human T-cell transcription factor NFAT1 has been reported to regulate cell cycle regulatory proteins including Cyclins A, D, and p21. This group has recently identified microRNA-184 to regulate NFAT1 protein translation in human umbilical cord blood CD4 T-cells. We sought to determine if NFAT1 protein expression is dysregulated in T-ALL, and if so, its contribution, if any to T-ALL pathogenesis.

Materials & Method:
MOLT-4 cells were maintained according to ATCC guidelines. Normal adult and umbilical cord blood (UCB) T-cells were selected by AutoMACS (Miltenyi Biotec) and and maintained per standard protocols. Purity was confirmed in excess of 90% by flow cytometry. MOLT-4 cells were transfected with a 10 pmol:3.33 pmol ratio of anti-miR-184 miRNA inhibitor (Ambion) to siGLO non-specific RISC-free control (Dharmacon) in complete RPMI alongside corresponding controls via lipofectamine RNAi max (Invitrogen) overnight per manufacturers’ instructions. Protein was isolated 48 hours after transfection and quantified by standard protein assay (BioRad). 10 μ g of each fraction was analyzed by 10% SDS-PAGE followed by Western Blotting with anti-NFAT1 (BD Biosciences) and γ-tubulin (Santa Cruz Biotechnology) antibodies. Bands were visualized using Supersignal West Pico chemiluminescent substrate (Pierce).

Result:
The relative levels of both NFAT1 protein and mir-184 were first compared to normal adult and UCB CD4+ T-cells. As miR-184 and NFAT1 expression levels can change over the developmental life of CD4+ T-cells, a comparison of MOLT-4 cells was made to normal UCB T-cell controls with similar surface phenotypes (CD4+/8+). NFAT1 protein expression was found to be significantly decreased in the MOLT-4 cells by Western Blot. Further, comparisons of miR-184 expression in UCB double positive T-cells to MOLT-4 by quantitative reverse transcription real-time PCR (qPCR) demonstrated a 56-fold higher expression of mir-184 in MOLT-4 compared to controls. Next, in order to test the ability of miR-184 to regulate NFAT1 levels in the MOLT-4 T-ALL cell line, lipofectamine-mediated transfections of antisense miR-184 were performed. Western Blot analysis showed the expected modest increase in the NFAT1 protein expression in MOLT-4 cells transfected with anti-miR-184.

Discussion:
NFAT1 protein levels are notably reduced in T-ALL cell lines and may be attributable in part to 56-fold higher expression of miR-184. Knockdown of miR-184 renders normalization of NFAT1 protein levels. Ongoing studies are designed to determine cell cycle kinetics and p21 expression in miR-184 transfected MOLT-4 cells. Dysregulation of NFAT1 may contribute to T-ALL pathogenesis, and miR-184 regulation of NFAT1 may be a target for therapeutic studies.

Disclosures:
No relevant conflicts of interest to declare.
Successful Treatment of Acute Promyelocytic Leukemia (APL) In a Patient with Severe Cardiac Disease
Authors: Ayalew Getinet D. , Rotkowitz Michael I. , Mittal Juhi , Sidhu Gurinder , Braverman Albert S. , Khillan Ratesh 
Published: October 2019

Abstract
Abstract 4369

Background:
The standard and often curative regimen for APL includes cardiotoxic daunorubicin and All-Trans Retinoic Acid (ATRA). Arsenic trioxide (ATO), like ATRA, induces leukemic blast differentiation and is active in APL.

Case Report:
A 58 year old African American man had a metallic aortic valve replacement 6 years prior to presentation, for which he was on warfarin, coronary artery disease, a left ventricular ejection fraction of 20%, and an implanted cardioverter-defibrillator. He presented with dyspnea, fever, scattered rales and ecchymoses and petichiae. His white blood count was 38,000/mcl, with 51% promyelocytes and 8% neutrophiles, Hb 9.7 g/dl, and platelets of 12,000/mcl. Fibrinogen was 172 mg/dl, aPTT 28 seconds, and international normalized ratio 2.3; lactate dehydrogenase was 1593 U/dl. The bone marrow (BM) was replaced by promyelocytes, karytotype revealed t (15;17) (q22;q12), and fluorescent in situ hybridization (FISH) showed the promyelocytic leukemia – retinoic acid receptor fusion product (PML-RARA). The diagnosis was high risk APL. Warfarin was suspended, and treatment was initiated with ATRA 45 mg/M2. On day 7, he developed shortness of breath; cough and chest radiograph illustrated marked interstitial edema as well as bilateral pleural effusion. These features of the differentiation syndrome resolved rapidly after transfer to the Medical Intensive Care Unit and dexamethasone initiation. On day 10, daily ATO at 0.15 mg/kg IV was initiated. His QTC interval ranged from 430–600 ms, showed interactions with 5-HT inhibitors and antifungal drugs, and stabilized after discontinuation of these drugs. By day 23, his white blood cell counts had normalized, and BM aspiration showed normal morphology. ATO was discontinued, platelet count rose to 50,000/mcl by day 28, when warfarin was resumed. Post-induction the patient received 4 cycles of ATO 5 days per week for 4 weeks, each followed by 4 weeks off treatment and ATRA 45 mg/m2 daily for 2 weeks every 4 weeks for a total of 7 cycles. Cytogenic remission was confirmed by FISH analysis of BM on days 23 and 113, and subsequently by quantitative RT-polymerase chain reaction on peripheral blood specimens for one year. By these criteria he remains in complete remission one year after presentation.

Conclusion:
With careful cardiac monitoring, ATRA-ATO induced a durable complete remission of APL in a patient with several major cardiac contra-indications to anthracyclines. Despite the patient's metallic aortic valve, he tolerated suspension of anti-coagulant therapy well.

Disclosures:
No relevant conflicts of interest to declare.
Effect of Heparin:PMX60056 Complexes on Platelet Aggregation Induced by ADP or HIT Antibody
Authors: Jeske Walter , McAllister R. Eric , Walenga Jeanine M. , Paulus Michelle , Fareed Jawed 
Published: October 2019

Abstract
Abstract 4386

Introduction:
A neutralization of anticoagulant activity occurs when heparin binds to a variety of positively charged substances such as protamine and platelet factor 4 (PF4). PMX60056 (PolyMedix, Radnor, PA) is a novel compound that is being developed as a heparin antagonist. Since heparin-PF4 complexes are antigenic, with antibodies against this complex activating platelets to trigger thrombin generation, thrombus formation and associated morbidities, it is of interest to determine whether heparin:PMX60056 complexes affect platelet function. This study compares the effect of PMX60056 and protamine, alone and complexed to heparin, on platelet function as assessed by platelet aggregometry.

Materials and Method:
Whole blood, collected from 10 healthy individuals, was anticoagulated with 3.2% sodium citrate and centrifuged to make platelet rich plasma (PRP). PRP was supplemented with 10 μ g/ml heparin (~1.5 IU/ml), 10 μ g/ml heparin antagonist (protamine or PMX 60056) or a complex of 10 μ g/ml heparin and 10 μ g/ml heparin antagonist. Platelet aggregation was stimulated by the addition of ADP (5 or 10 μ M final concentration) or serum from a patient with heparin-induced thrombocytopenia.

Result:
ADP-induced platelet aggregation was not affected by the addition of heparin, protamine, PMX 60056, or complexes of heparin with heparin antagonist. In the HIT system, heparin + HIT serum led to a significant increase in platelet aggregation vs. saline (46.7 ± 3.2 % vs. 8.2 ± 2.9%). HIT serum + heparin antagonist did not induce platelet aggregation (PMX60056: 10.2 ± 4.4%; protamine: 11.6 ± 3.5%). The aggregation responses to HIT serum + heparin (46.7 ± 3.2%), HIT serum + heparin:PMX60056 (43.6 ± 5.8%) and HIT serum + heparin:protamine (47.8 ± 3.8%) were not significantly different.

Conclusion:
When mixed at equigravimetric amounts, protamine and PMX60056 do not prevent formation of immune complexes consisting of HIT antibody and heparin which lead to platelet activation. Previous data from human trials has suggested that smaller amounts of PMX60056 (less than equigravimetric) may effectively neutralize heparin. Thus, it is speculated that smaller heparin:PMX60056 complexes may induce less antibody formation than larger heparin:protamine complexes. Validation of this hypothesis in animal models or clinical studies is warranted.

Disclosures:
McAllister: PolyMedix, Inc.: Employment.