bluuebunny/crossref_metadata_2025_split huggingface dataset:
Establishing a New Zebrafish Model to Study Malignant Transformation in Myeloproliferative Disorders
Authors: Alghisi Elisa , Malagola Michele , Santoriello Cristina , Skert Cristina , Filì Carla , Bergonzi Cesare , Peli Annalisa , Turra Alessandro , Cancelli Valeria , Ribolla Rossella , Cattina Federica , Mione Marina , Russo Domenico 
Published: October 2019

Abstract
Abstract 4711

Background:
Myeloproliferative diseases (MPDs) are a group of hematological malignancies characterized by the abnormal increase of different blood cells in peripheral blood and in other hematological organs. The molecular pathways involved in disease pathogenesis and progression as well as in drug sensitivity and resistance are not fully elucidated yet. Given the physiological similarity to mammals, the zebrafish (ZF) could accelerate the study of the molecular basis of these diseases. In the last decade several human leukaemia associated oncogenes have been transiently over-expressed in ZF embryos in order to perturb the myelo-erythroid compartment, with the aim to create experimental models to discover new molecular pathways that can became potential targets for new chemical compounds.

Methodogy:
We took advantage of the binary Gal4/UAS system to express oncogenic human HRAS in the ZF hematopoietic compartment. We used the tg(MAZe) driver line, a specific transgenic line that allows random mosaic expression of Gal4-VP16 after heat shock(hs) treatment(1). This driver line was mated with a tg(UAS:eGFP-HRASV12)(2) responder line in order to mimic somatic events leading to human oncogene expression.

Results:
Surprisingly a single heat shock at 30hpf, (referred here as HRASV12hs) induces human HRASV12 expression in hematopoietic progenitors as judged by the expansion of the hematopoietic tissue. Histological analysis showed an increased number of monocytes/macrophages. Blood smear of HRASV12hs larvae showed the expansion of blasts and myeloid precursors. Quantitative analysis of gene expression highlights a remarkable increase of myelo-erythroid restricted genes associated with a slight increase of staminality markers (pu1, mpx, lmo2, mpl, CD41 and c-myb). Moreover fish raised to adulthood developed hyper-plastic kidney marrow, the site of definitive haematopoiesis, the equivalent of mammalian bone marrow.

Conclusions and Future Perspectives:
The combination of hyper-proliferation of blood cells associated with the expansion of the hematopoietic compartment that we found in this model reproduces the pathological features of human myeloproliferative disorders. This study shows that it is possible to drive the expression of leukemia associated oncogenes to the hematopoietic compartment in developing ZF thus reproducing some of the features of human blood malignancies in an in vivo model. Our Group is now testing different driver lines in order to induce oncogene expression in earliest hematopoietic progenitors and is focusing on different responder lines expressing human oncogenes involved in hematopoietic malignancies.

Disclosures:
No relevant conflicts of interest to declare.
CD80-IL2 Expressing Myeloma Cells for Immune Gene Therapy of Multiple Myeloma
Authors: Giunti Giulia , Malone David , Chan Lucas , David Darling , Kordasti Shahram Y , Barber Linda , David Oppenheim , Farzaneh Farzin , Schey Stephen 
Published: October 2019

Abstract
Abstract 4718
Improved experimental therapies are needed for Multiple Myeloma (MM). Despite major progress in treatment and initial induction of remission, myeloma remains an incurable disease. Although immunotherapy and, in particular, the employment of NK cells offers an approach of interest for the treatment of Multiple Myeloma (MM), recent studies have shown that myeloma cells utilise a number different mechanisms to impair NK and T cell functions. Important amongst these mechanisms is the reduced expression of CD80 in the sub-populations of PBMC isolated from myeloma patients.
We have previously demonstrated CD80/IL-2 mediated stimulation of NK and T cells isolated from AML patients (as measured by proliferation, cytokine release and target cell specific cytolytic activity). In the present study we have examined the ability of genetically modified MM cells engineered to express CD80 and IL-2 to stimulate NK cell functions. These studies confirm the ability of MM cells to suppress NK cell functions in healthy PBMC and show that in contrast to the unmodified MM cells, the CD80/IL-2 expressing MM cells are able to stimulate a moderate increase in NK and T cell numbers and a significant increase in the fraction of NK cells with activatory receptors (NKp44, NKp30, NKp46) and activation markers (CD69) on the cell surface of both NK and T cells. More importantly for potential therapeutic applications the stimulated NK cells show increased cytolytic activity against the unmodified MM cells.
This data suggest that CD80/IL-2 MM cells may be able to overcome the immune suppressive functions of unmodified MM cells and to stimulate NK, and T cell mediated responses against the unmodified MM cells. Therefore CD80/IL-2 expressing MM cells may provide a suitable cellular vaccine for NK cell stimulation and possibly the induction of broader ranging immunological responses against multiple myeloma cells.

Disclosures:
No relevant conflicts of interest to declare.
Dexamethasone Reduces Viability of Bone Marrow Derived Macrophages
Authors: Ohana Yasmin , Souroujon Miriam C , Mittelman Moshe , Neumann Drorit 
Published: October 2019

Abstract
Abstract 4732
Glucocorticoids are steroid hormones with pleotropic effects and are widely used in clinical practice. Glucocorticoids affect almost every cell of the immune system. Here, we show that dexamethasone (DEX), a synthetic glucocorticoid, decreases viability of naïve bone marrow-derived macrophages (BMDM) in a dose dependent manner. A 24-hour incubation with 0.1, 0.5 and 1 microM DEX reduced BMDM viability by 22%, 26% and 34%, respectively, compared with untreated cells. Annexin-PI staining suggests an apoptotic mechanism. Administration of DEX in the presence of lipopolysaccharide (LPS) protected the BMDM against DEX-mediated cell death.
In addition to its effect on cell viability, DEX also significantly reduced the percentage of BMDM expressing high levels of the differentiation and activation markers F4/80 and CD11b (5 fold decrease mediated by 1 microM DEX). Treatment of BMDM with 1 microM DEX also led to a ∼ 50% decrease in macrophage inflammatory protein 1 alpha (MIP-1-alpha) mRNA expression levels.
These findings may contribute to a better understanding of DEX effects on naïve and activated macrophages and may have clinical implications in various diseases, including infection, inflammation and neoplastic diseases.
Glucocorticoids are steroid hormones with pleotropic effects and are widely used in clinical practice. Glucocorticoids affect almost every cell of the immune system. Here, we show that dexamethasone (DEX), a synthetic glucocorticoid, decreases viability of naïve bone marrow-derived macrophages (BMDM) in a dose dependent manner. A 24-hour incubation with 0.1, 0.5 and 1 microM DEX reduced BMDM viability by 22%, 26% and 34%, respectively, compared with untreated cells. Annexin-PI staining suggests an apoptotic mechanism. Administration of DEX in the presence of lipopolysaccharide (LPS) protected the BMDM against DEX-mediated cell death.
In addition to its effect on cell viability, DEX also significantly reduced the percentage of BMDM expressing high levels of the differentiation and activation markers F4/80 and CD11b (5 fold decrease mediated by 1 microM DEX). Treatment of BMDM with 1 microM DEX also led to a ∼ 50% decrease in macrophage inflammatory protein 1 alpha (MIP-1-alpha) mRNA expression levels.
These findings may contribute to a better understanding of DEX effects on naïve and activated macrophages and may have clinical implications in various diseases, including infection, inflammation and neoplastic diseases.v

Disclosures:
No relevant conflicts of interest to declare.
Neutropenia Does Not Delay Lymphopoietic Regeneration in NODSCIDcγ−/− Mice
Authors: Bugl Stefanie , Wirths Stefan , Martin R Müller , Melanie Märklin , Wiesner Tina , Malenke Elke , Kopp Hans-Georg 
Published: October 2019

Abstract
Abstract 4831

Introduction:
Previously it was demonstrated that lymphopoiesis is rapidly established after transplantation of wild type stem cells into lymphopenic NODSCIDcγ−/− mice. These data were interpreted as evidence for an “empty” preformed lymphopoietic niche being replenished by lymphoid progenitors. We hypothesized that antibody-induced neutropenia might influence early post transplant fate decision to myeloid rather than lymphoid differentiation resulting in delayed lymphoid reconstitution.

Materials and Methods:
25,000 flow sorted CD45.2-expressing wild type Lin-/Sca1+/c-Kit+ (LSK) cells from C57BL/6 mice were transplanted into sublethally irradiated B-/T-/NK-cell deficient NODSCIDcγ−/− mice (CD45.1). Three groups of n = 7 mice received anti-Gr1 or anti-1A8 i.p. every 48 h to induce continuous antibody-mediated neutropenia vs. PBS as control. Blood was harvested at regular intervals to monitor the engraftment. After 16, 22, and 34 days, animals were sacrificed and underwent blood and bone marrow analysis.

Results:
Hematopoietic regeneration started with the emergence of donor-derived monocytes in all groups as well as neutrophils in the control group as early as 9 days after transplantation. On day 14, B cells were to be detected for the first time, followed by T lymphocytes approximately 20 days after transplantation. Besides the fact that neutrophils were undetectable in the antibody treated groups, the peripheral blood revealed no significant changes between the neutropenic mice and the control group at any point of time. At the bone marrow level, an increase of LSK and granulocyte-macrophage progenitors (GMPs) at the expense of megakaryocyte erythrocyte progenitor cells (MEPs) was found in neutropenic mice. Common lymphoid progenitors (CLPs), however, were not significantly different.

Conclusions:
The engraftment of wild type donor cells after hematopoietic stem cell transplantation into NODSCIDcγ−/− mice started with the production of monocytes and neutrophils. B-lymphocytes were detectable by day 14 after transplantation. The production of T-cells started around day 20. Continuous antibody-mediated neutropenia did not significantly delay lymphoid regeneration. Although the marrow of neutropenic mice displayed increased proliferation of granulocyte progenitors, CLPs were unchanged. We conclude that the detection of donor-derived lymphocytes in the host peripheral blood is a relatively early event after LSK transplantation. Moreover, antibody induced neutropenia is not sufficient to induce sustainable changes in early hematopoietic fate decisions on the bone marrow level.

Disclosures:
No relevant conflicts of interest to declare.
Hodgkin Lymphoma in Jordan; A Retrospective Analysis of 477 Cases in King Hussein Cancer Centre
Authors: Addasi Alaa 
Published: October 2019

Abstract
Abstract 4862

BACKGROUND
Jordan is a small country with an estimated mid year population in 2008 of 5 850 000, 3015000 of whom are males and 2 835 000 are females (male: female ratio 1.06: 1). (Department of Statistics Jordan, 2008).
About 12.7 % of the population is under 5 years old, and 37.3 % under 15 years old. 11%if the population are 15–19 year old, with a M:F ratio 1.06:1 as well) Only 3.3 % of the total population is above the age of 65 years old (sex ratio of 1.01 male per 1 female in this age group).
According to the Jordan Cancer Registry Report for 2008, Lymphoma is the fourth most common Cancer in the country. A total of (4606 ) new cases of cancer were recorded among Jordanians in the year 2008, 333 (7.2%) of whom had a diagnosis of lymphoma.111 (2.4%) were diagnosed as Hodgkin's lymphoma (HL), and 222 (4.8%) as Non Hodgkin Lymphoma(NHL).

OBJECTIVE
In this study, we aim to characterize some of the clinico-pathological features of Hodgkin lymphoma in Jordan by analyzing the data available for patients referred to King Hussein Cancer Center over a seven year period.

PATIENTS AND METHODS
A retrospective analysis was conducted of adults (>18 years) lymphoma patients referred to KHCC, between 1/1/2003 and 31/12/2010. Clinical features and histological subtypes were prospectively established for all patients registered in the Lymphoma Service Database. Pathology review and original paraffin block were mandated for all patients.

RESULTS
Over the 8 year period of 2003–2010,1329 lymphoma patients were referred to KHCC and registered in the Lymphoma Service Database, of whom 477 (35.9%) were diagnosed with Hodgkin's lymphoma. Among this group all 477 patients were adults 18 years or older (100%), as children are treated in a different department. The median age was 35 years, (with an age range of 18–77), and 5% of patients were above the age of 60. 290 (61 %) of the patients were males, 187 (39%) were females, with a male to female (M:F) ratio of 1.55:1.
276 (57.8%) of the HL cases had a diagnosis of nodular sclerosis Hodgkin lymphoma (HDNS), making it the most common histological subtype. 120(25.2%) had mixed cellularity Hodgkin lymphoma (HDMC), 9 (1.9%) had lymphocyte-rich Hodgkin lymphoma (HDLR), and 6 (1.2%) had lymphocyte-depleted Hodgkin (HDLD). Nodular lymphocyte predominance Hodgkin lymphoma (NLPHD) cases were 33, and constituted 6.9% of the HL cohort.

CONCLUSION
Hodgkin lymphoma appears to constitute a bigger share of the lymphoma burden in Jordan, as opposed to Europe and the US. Clinico-pathological features, however, appear to be closer to those described in Western countries, with similar incidence of HDNS, and HDMC subtypes, but possibly with less incidence of HDLR and HDLD subtypes.

Disclosures:
No relevant conflicts of interest to declare.
Trisomy 8 Remains An Intermediate Cytogenetic Risk Factor in Patients with Acute Myeloid Leukemia (AML) Treated with Stem Cell Transplantation
Authors: Walter Claudia Ulrike , Almhareb Fahed , Chaudhri Naeem A. , Zahrani Hazzaa Al , Bakr Mohammad , Ibrahim Khalid , Hussain Fazal , Mohamed Said , Rasheed Walid , Alsharif Fahad , Aljurf Mahmoud , Albitar Maher 
Published: October 2019

Abstract
Abstract 4900

Background:
Trisomy 8 is the most common chromosomal change in AML, as sole aberration in 5 % of cytogenetically abnormal cases and occurring together with other abnormalities in an additional 10% and little is known about the pathogenetic impact of trisomy 8. Most studies reported trisomy 8 in AML to be associated with intermediate risk. However, some reports have identified a poorer outcome than is usually seen in the intermediate group, considering trisomy 8 an adverse prognostic factor. More importantly, the clinical behavior and outcome of patients with trisomy 8 who are treated with hematopoietic stem cell transplantation (HSCT) is not known. We investigated the outcome in patients with trisomy 8 who were treated with HSCT.

Methods:
Bone marrow conventional cytogenetic and FISH data from 110 adult AML patients was reviewed and patients divided into three cytogenetic risk groups according to the European LeukemiaNet reporting system while separating patients with trisomy 8 into another, fourth, independent group. Patients with trisomy 8 as part of a complex karyotype (complex = 3 or more abnormalities) were excluded. We also compared outcome of patients with trisomy 8 to the intermediate-risk group alone and adverse-risk group alone, respectively. The AML cohort included 62 (56%) patients treated in their first remission (CR1) while most non-CR1 AML patients were treated with HSCT in CR2. The median age of all patients was 25 years (range: 14–58).

Results:
Patients with trisomy 8 were 9 (8%). Patients with trisomy 8 showed significantly longer overall survival (OS) (P=0.02) and event-free survival (EFS) (P=0.03) as compared to patients with adverse cytogenetics. The outcome of trisomy 8-positive patients was similar to the intermediate-risk group.

Conclusions:
This data suggests that trisomy 8 in AML is an intermediate-risk factor when patients are treated with HSCT. While we did not compare the outcome of HSCT with the outcome of trisomy 8-positive patients treated with intensive chemotherapy, most likely the cytogenetic risk of trisomy 8 for patients after HSCT is similar to their cytogenetic risk when treated with chemotherapy.

Disclosures:
No relevant conflicts of interest to declare.
Evaluation of the Intra-LABORATORY Reproducibility of Percentage of Blast Counting In MYELODYSPLASIA
Authors: Wuilleme Soraya , Eveillard Marion , Barillet Sophie , Accard Françoise , Avet-Loiseau Hervé , Delaunay Jacques , Garand Richard 
Published: October 2019

Abstract
Abstract 4901
In the two International Prognostic Scoring Systems of Myelodysplastic Syndrom (MDS), the percentage of BLAST cells in the Bone Marrow is the most important parameter implicated in score: either directly in the IPSS (International Prognostic Scoring System) (1) or indirectly in the WPSS (Who classification-based prognostic scoring system) (2). In these two systems, as in the recommendations of the WHO 2001 (3), the morphological criteria defining blasts cells compared to promyelocyte cells are not specified. In 2005, the IWGM-MDS (International Working Group on Morphology of myelodysplastic syndrome) (4-6) has established morphological criteria defining Blasts cells.
Our objective in this study is to evaluate the reproducibility, among five observers of our laboratory, of the counting of the marrow blasts of 73 myelodysplasia. This study was conducted in several stages. 1st step was to test the implementation of the MDS-Foundation (www.mds-foundation.org/virtualmicroscopy) by 5 observers. The 2nd step was to perform correlation test of the selected cells from RAEB (selected and stained in our laboratory conditions), for the 5 observers. Finally Step 3 was to assess the correlation of blast percentage of 73 bone marrow smears from MDS patients, selected due to the presence of an excess of blast cells in the first reading on the bone aspiration.
Our results show that the correlation on counting blasts is generally satisfactory (percentage agreement: Test 1 = 86% and test 2 = 94%), while the concordance on the counting blasts of bone marow smears of 73 MDS patients and concordance on the WHO classification seems less satisfactory (agreement 3/5 observers. = 95% but agreed to 4–5/5 observers = 64%). These results can be explained partly by the inter-observer variability and by the variability of some parameters specific to smear marrow (poor quality smears, the staining and/or poverty of smears).
In conclusion, the evaluation of the blasts in the MDS must be achieved: (i) at least 500 cells counted (ii) by at least two different observers (iii) by a third observer in discordant case. Despite these recommendations, the assessment of the blasts in myelodysplasia is difficult to achieve in many cases.

Disclosures:
No relevant conflicts of interest to declare.
Bendamustine for Mantle Cell Lymphoma: Retrospective Analysis of the Spanish Experience
Authors: García-Noblejas Ana , Navarro Matilla Belén , Da Silva Rodriguez Carolina , De Oña Navarrete Raquel , Ramirez Sánchez María José , Nicolás Concepción , Pérez Fernández Ricardo , Sanchez Gonzalez Blanca , Domingo-Domènech Eva , Sanchez Blanco Jose Javier , Cannata-Ortiz Jimena , González-López Tomás José , Arranz Sáez Reyes 
Published: October 2019

Abstract
Abstract 4942

INTRODUCTION.
Patients with Mantle cell lymphoma (MCL) have an adverse outcome after relapse due to chemorefractory disease with conventional treatments. Bendamustine, a nitrogen mustard compound chemically related to the alkylating agents, has demonstrated high efficacy with a low toxicity profile in reported clinical trials.

AIM.
To analyze the Spanish experience in patients with relapsed/refractory MCL treated with Bendamustine.

METHODS.
Retrospective analysis of spanish experience in relapsed/refractory MCL treated with Bendamustine alone or in combination. This study has been approved by local ethical committees.

RESULTS.
Currently, there are 36 patients registered and 28 are available for this analysis. Patients'characteristics: 69% male, median age 65 years old (range 41–81), 87% ECOG≤ 1, 83% Ann Arbor stage IV, 37% high risk MIPI and 9% blastic variant. Previous regimens were CHOP or CHOP like ± R in 42.5%, HyperCVAD/MtxAraC ± R in 42.5%, R-CVP in 9% and other regimens in 6%. Median number of previous treatments were 2.6 (range 1–6), all patients had received prior Rituximab and 73% had chemosensitive disease to the last treatment. Bendamustine regimen was R-B (R-375mg/m2 D1, B-90 mg/m2 D1-2) in 78% patients, R-B with B-70 mg/m2 in 8%, B alone in 3%, R-B-Bortezomib in 3% and R-B plus consolidation (SCT, Y90Ibritumomab-tiuxetan) in 8%. Median number of cycles was 4.61 (range 1–7). G- CSF support was administered in 43% of cycles. Response: Overall response rate was 73%, with 43% CR & uCR and 30% PR. Survival: Median overall survival from diagnosis is 8,26 years (range: 1.6–11,6 years) without plateau. Median progression free survival (PFS) after Bendamustine treatment was 16 months (95% CI: 11.7–20.4), data that compares favourably with patients' PFS to previous therapy (12 months, 95% CI: 6.5–17.5). Median PFS for patients who achieved CR/uCR is 32.6 months (95% CI: 19.9–45.4) versus 11 months in patients with PR (95% CI: 3.9–18.8). With a median follow-up for surviving patients of 12 months since Bendamustine treatment, the estimated OS at 3 years is 47% (+ SD 14%). Toxicity: No treatment related mortality has been described so far. Over 152 cycles, only 10 hospitalizations due to febrile neutropenia were reported. No one case of lysis tumoral syndrome has been reported.

CONCLUSION.
Bendamustine plus Rituximab is a good rescue treatment in non selected pretreated patients with mantle cell lymphoma. CR rate and duration of response seem to reproduce in current clinical practice the good data reported in previous clinical trials and compares favourably with other available treatments.

Disclosures:
No relevant conflicts of interest to declare.