bluuebunny/crossref_metadata_2025_split huggingface dataset:
Outcome of Refractory Anemia with Ringed Sideroblasts Associated with Marked Thrombocytosis (RARS-T) In a Large Cohort of Patients
Authors: Girodon Francois , Broseus Julien , Florensa Lourdes , Zipperer Esther , Schnittger Susanne , Malcovati Luca , Richebourg Steven , Lippert Eric , Cermak Jaroslav , Nangalia Jyoti , Mounier Morgane , Raya Jose Maria , Gattermann Norbert , Haferlach Torsten , Cazzola Mario , Garand Richard , Kaoutar Allou , Maynadie Marc , Besses Carlos , Germing Ulrich , Haferlach Claudia , Travaglino Erica , Hermouet Sylvie 
Published: October 2019

Abstract
Abstract 4113

Introduction:
Most of the data related to RARS-T, a rare disorder, involve small cohorts of patients. We aimed to analyze more patients also considering a variety of myelodysplastic or myeloproliferative disorders.

Objective:
To compare a large cohort of patients with RARS-T to refractory anemia with ringed sideroblasts (RARS), refractory anemia with ringed sideroblasts and multilineage dysplasia (RARS-MD) or essential thrombocythemia (ET) at the time of diagnosis and during disease evolution, in terms of survival and complications.

Materials:
Data of a European multi-center study was used including 199 cases of RARS-T 173 cases of RARS, 102 cases of RARS-MD and 431 cases of ET.

Results:
At baseline, compared to RARS and RARS-MD patients, RARS-T patients had similar hemoglobin concentration, but a higher white blood count. The JAK2V617F mutation was observed in 43%, 12% and 5% in RARS-T, RARS and RARS-MD patients, respectively. When separated in 2 groups (450,000<platelet count <600,000 and platelet count >600,000 × 109/l), RARS-T patients were comparable for sex, age, hemoglobin level and survival. However, patients with platelet count > 600,000 × 109/l had higher WBC (11 ×109/l versus 7.5 ×109/l, p<0.001). Similarly, no difference was noted in the survival in the JAK2 positive and negative RARS-T patients. The age and sex standardised overall survival of RARS-T patients was similar to RARS and RARS-MD patients, but lower than ET patients (p<0.001). This was despite a higher risk of transformation in acute leukemia, relative to RARS-T afflicted individuals, of 2.4 and 3.5 in RARS-MD and RARS patients, respectively.

Conclusion:
According to our results, the outcome in RARS-T more closely mimics myelodysplastic syndromes rather than myeloproliferative neoplasms. Our results agree with the WHO 2008 classification that considers RARS-T as a separate disorder.

Disclosures:
Schnittger: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Gattermann:Novartis: Honoraria, Research Funding. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.
Prognostic impact of circulating Epstein-Barr virus (EBV) DNA concentration and EBV serology in 125 extranodal NK/T cell lymphoma, nasal type (ENKL) patients
Authors: Guo Chengcheng , He Huang , Guo Hongqiang , Xiao Jian , Zhang Yujing , Tian Ying , Cao Yabing , Fu Xiaohong , Zhai Linzhu , Lin Tongyu 
Published: October 2019

Abstract
Abstract 4148

Background
extranodal NK/T cell lymphoma, nasal type (ENKL) has worse efficacy and prognosis than B-NHL. Circulating EBV DNA concentration can reflect the efficacy and prognosis in some EBV related malignance (nasopharyngeal carcinoma). But there are few studies about the relation between EBV infection and ENKL. This prospective study is to confirm predictive value of circulating EBV DNA concentration and EBV serology in ENKL patients.

Methods
In the prospective study, serum samples from 125 previously untreated ENKL patients were collected from Jan 2002 to Dec 2006. We detect VCA-IgA and EA-IgA level by immunoenzyme methods and circulating EBV DNA concentration by real-time PCR assay. All patients were received long-term efficacy and survival assessment.

Results
The median follow-up time is 4.53 years. The positive rates of VCA ƒüIgA and EA ƒüIgA are 30.6% and 1.6% respectively, both of which could not predict the efficacy and survivals. The positive rate of circulating EBV DNA is 69.4%, with a median concentration of 13400 copies/ml. Patients with extranodal involvement, B syndrome, upper respiratory involvement, neutropenia or anemia or thrombocytopenia, liver dysfunction, and increasing of β2MG, have significantly higher EBV DNA positive rate(45.1% A54.4% A62.3% A53.5% A90.0% A59.3%, respectively). Patients in higher EBV DNA concentration group is easier to have bone and/or skin involvement (≤13400 copies/ml group: 45.8%vs. >13400 copies: 16.0%, p=0.024). The positive circulating EBV DNA group has a lower complete remission (CR) rate (38.8%vs.59.2%, p=0.026), higher relapse rate (52.6%VS.26.7%, p=0.046) than negative one. The 5-year DFS and 5-year OS decreased with the dose of circulating EBV DNA group (DFS: negative group74.3% vs. ≤13400 copies/ml group 55.0% vs. >13400 copies/ml group 28.6%, p=0.003; OS: negative group 55.8% vs. ≤13400 copies/ml group 48.4% vs. >13400 copies/ml group 29.2%, p=0.004).

Conclusions
The positive rate of circulating EBV DNA is much higher in ENKL. Circulating EBV DNA concentration, as measured by real-time PCR, is a useful tumor marker for diagnosis and prognostication with ENKL patients. Patients with higher dose of circulating EBV DNA level (>13400 copies/ml) may undergo more aggressive biological behavior.

Disclosures:
No relevant conflicts of interest to declare.
Incidence and Risk Factors for Central Nervous System (CNS) Relapse In Patients with Diffuse Large B-Cell Lymphoma (DLBCL): Analysis with Competing Risk Regression (CRR) Model
Authors: Chihara Dai , Oki Yasuhiro , Matsuo Keitaro , Onoda Hiroshi , Taji Hirofumi , Yamamoto Kazuhito , Morishima Yasuo 
Published: October 2019

Abstract
Abstract 4154

Introduction:
CNS relapse is a challenging complication in patients with DLBCL. Identification of high risk population is therefore critical, in whom prophylactic intrathecal (IT) chemotherapy may play a significant role. To calculate the cumulative incidence of CNS relapse, Kaplan-Meyer method tends to overestimate the incidence because a censored individual by death is still assumed to have a chance to fail from CNS relapse. To overcome this methodological conflict, we evaluated the risk factors for CNS relapse in patients with DLBCL using CRR analysis.

Methods:
Medical records of patients with DLBCL newly diagnosed and treated with CHOP or R-CHOP at Aichi Cancer Center Hospital between 1995 and 2008 were reviewed. Patients were excluded if they had evidences of CNS involvement at initial diagnosis.

Results:
A total of 386 patients who met the criteria for the study were analyzed. The median age of patients was 62 (range 18–95). All patients received CHOP based systemic chemotherapy with (n=203) or without (n=183) rituximab. Prophylactic IT chemotherapy was provided to 6 patients with testicular involvement. At a median follow up duration of 52.9 months, 24 patients experienced CNS relapse. Nine patients presented with brain parenchymal mass, 12 patients presented with leptomeningeal disease, and 3 patients presented with both. The median time from initial diagnosis to CNS relapse was 20.5 months (range 5.3–91.8 months). Five-year cumulative incidence of CNS relapse was 6.7% (95%CI: 4.2–9.8). Five-year cumulative incidence of CNS relapse in patients treated with and without rituximab was 5.9% and 7.3%, respectively (p=0.42). Multivariate analysis for the risk factors of CNS relapse using CRR identified three independent risk factors for CNS relapse; bulky disease (SHR 3.34 [1.45-7.66], p=0.004), lymphocyte count<1.0 ×109/L (SHR 2.38 [1.05-5.39], p=0.017) and extranodal involvement (SHR 2.90 [1.01-8.33], p=0.047). Patients with all three risk factors represented 6% of all patients, in whom the 5-year cumulative incidence of CNS relapse was 26% (Figure 1). When the number of extranodal involvement was taken into account, patients with 3 or more sites of extranodal involvement had extremely high incidence of CNS relapse (28%), all occurring within 18 months after initial diagnosis. These patients may be good candidates for CNS evaluation at initial diagnosis even in the absence of neurological manifestation.

Conclusions:
We identified significant risk factors for CNS relapse in patients with DLBCL using CRR. Evaluation for CNS involvement and prophylactic IT chemotherapy should be considered in patients with high risk features.

Disclosures:
No relevant conflicts of interest to declare.
In Vivo Monitoring of Venous Thrombosis In Mice Using Ultrasonography
Authors: Aghourian Meghedi , Lemarie Catherine , Blostein Mark 
Published: October 2019

Abstract
Abstract 4214
Deep venous thrombosis is an important cause of morbidity and mortality in clinical medicine. There has been extensive research dedicated to the clinical aspects of venous thrombosis, especially with regards to its diagnosis and treatment. However, animal models studying this phenomenon are scarce and, in most cases, very crude, relying on sacrificing animals to excise the formed thrombi. Developing an in vivo murine model of venous thrombosis, detecting and monitoring thrombi non-invasively as is done in humans can be a powerful tool given our ability to genetically modify the murine genome. Therefore, we developed such a murine model using the Vevo770®, a microimaging ultrasound system previously developed to study the arterial circulation of mice. Two different thrombosis models were employed to generate clots in the inferior vena cava (IVC) of wild type C57Bl6 mice: 1) ligation of the IVC to generate venous stasis and 2) application of Ferric Chloride (FeCl3) to the outer layer of the IVC to injure the endothelium. Using both of these techniques, adequate thromboses were generated in the IVCs of mice as determined pathologically. Other mice were allowed to recover after surgery, and the development of venous thrombosis was assessed by ultrasonography using the Vevo 770®. In order to assess the precision of clot measurements using this novel technique, we then sacrificed the mice and excised the clots. In both models, the measurement of the clot pathologically correlates favorably (R2= 0, 9116 for the ligation model, and R2 = 0,905 for the FeCl3 model) with measurements done by ultrasonography (n=20 for the ligation model, and n=5 for the FeCl3 injury model). In the ligation model, a thrombus develops less than an hour after ligation of the IVC, and the size of the clot increases over time. For example, five hours after the ligation of the IVC, a clot develops and has a cross sectional area of 4,5 mm2. The clot size increases significantly (p=0.001) over time to 6.2 mm2 at 24 hours post ligation (n=20). Treatment of these mice with an anticoagulant (dalteparin at a dose of 200 u/kg) prior to the procedure prevented the development of IVC thrombosis as determined by ultrasonagraphy. These data suggest that the Vevo770® can be used as a reliable technique for the non-invasive assessment of venous thrombosis in mice. Developing a murine model for thrombosis using more accurate, and clinically more relevant techniques such as ultrasonography, is a step towards better understanding the pathophysiology of venous thromboembolism.
Figure 1. Clot length correlation using histology and ultrasonography, 24 hrs post ligation of the IVC in 20 mice. R2= 0,9116. Figure 1. Clot length correlation using histology and ultrasonography, 24 hrs post ligation of the IVC in 20 mice. R2= 0,9116.

Disclosures:
No relevant conflicts of interest to declare.
Epo Engages a Tnfr-13c Pathway to Advance for Primary Bone Marrow (Pro)Erythroblast Development
Authors: Singh Seema , Dev Arvind , Sathyanarayana Pradeep , McCrann Donald J , Emerson Christine , Pradeep Anamika , Wojchowski Don M. 
Published: October 2019

Abstract
Abstract 4238
In late stage erythroblasts, EPO can increase levels of Bclx, Bcl2 and/or Mcl1 anti-apoptotic factors. Proerythroblasts, however, are a key EPO target (and exhibit sharp dependence on EPO for growth, and survival). In these progenitors, however, Bclx, Bcl2 and Mcl1 are not prime EPO/EPOR targets. Via transcriptome-based analyses of EPO response circuits in developmentally staged primary bone marrow proerythroblasts (which we now analyze and present at a global level) an atypical TNF receptor, Tnfrsf13c proved to be among the top 1% of EPO/EPOR induced factors. Within lymphoid lineages, Tnfrsf13c is a known receptor for BAFF ligand; and BAFF is an essential mediator of B-cell survival and development. Possible effects of BAFF (a bone marrow stromal cell surface ligand) on primary erythroid cell formation therefore were assessed. Notably, limited BAFF exposure (15 hours) inhibited apoptosis; increased erythroid cell numbers; and enhanced the formation of late-stage Ter119pos erythroblasts. Specifically, cytoprotection by BAFF rivaled that afforded by EPO; cell numbers were enhanced 140% (in 15 hr); and frequencies of Ter119pos erythroblasts were enhanced to 200% of controls. In keeping with Tnfrsf13c's role as an EPOR target, each of the above effects further proved to depend upon proerythroblast exposure to EPO. With regards to Tnfrsf13c expression, analyses using primary erythroid progenitors with knocked-in minimal EPOR alleles indicated dependence for EPO- induction upon JAK2, STAT5 as well as EPOR C-terminal coupled pathways. Studies overall reveal a novel EPOR action route within primary proerythroblasts as a Tnfrsf13c/BAFF pathway (which engages non-canonical NF-kappaB molecular mechanisms).

Disclosures:
No relevant conflicts of interest to declare.
A Novel 3D Co-Culture System for Isolation and Amplification of Primary Liquid Cancer Cells
Authors: Caicedo-Carvajal Carlos , Liu Qing , Goy Andre , Pecora Andrew L , Mato Anthony R , Feldman Tatyana , Suh K. Stephen 
Published: October 2019

Abstract
Abstract 426
One of the important challenges in screening anti-cancer drugs is the lack of available “primary cultures systems” that is easy to use to screen new compounds or their combinations. The low yield of primary cancer cell cultures is mainly due to suboptimum environment in vitro and inefficient 2-dimensional cell culture conditions. To create an optimum in vitro environment, lymphoma cell lines were grown in 3-dimension model by using a scaffold and the stromal cells derived from neonatal foreskin was used as the feeder component. This 3-dimensional (3D) stromal co-culture generates an in-vitro model that may mimic the conditions/microenvironment of blood cancer cells interacting with stromal compartments. A specific 3D tissue culture scaffold 3D Insert-PS™ (300 μ m in fiber diameter and 400μ m in pore size) significantly enhances the cell proliferation and maintenance of liquid cancer cells in comparison to 2D stromal co-culture control. The combination of the neonatal stroma cells, a novel 3D scaffold, the constant gyration and a frequent nutrient stimulation allows the lymphoma cells to proliferate 10-fold faster than the cells grown in 2D under the same condition. Starting from the 2nd day of 3D cell culture, these lymphoma cells grew to form layers of aggregated clusters and caused disappearance of single cells morphology and phenotype that is typical of cells growing in suspension. The cell aggregates are continuously produced from the 3D scaffold, subsequently dislodge from the scaffold and then remain viable at the bottom of the dish below the scaffold. When the cell clusters are harvested and cultured in 3D condition, the contamination of fibroblasts is over 1,000 fold less than the cell clusters that are generated from 2D environment. In addition, the clusters of cancer cells generated from 3D co-culture using 3D scaffolds contained the fibroblasts contamination that is less than 0.00001% of the total cell count, suggesting that this novel 3D environment can be implicated for the isolation of primary lymphoma/cancer cells from patient's blood or tissue specimen. To investigate this feasibility, <1% lymphoma cells were premixed with 100 fold excess of neonatal stroma cells, and the mixture was grown using our 3D scaffolds. In 7 days, the 3D culture system was able to amplify lymphoma cells over 100 fold or over 10,000 % of the starting cell number. This preliminary data indicate that this 3D scaffold and co-culturing environment can be customized to amplify primary cancer cells from blood or tumor tissues and subsequently used for personalized drug screening procedures.

Disclosures: Goy:
Allos Therapeutics, Inc.: Consultancy, Honoraria.
Cardiac Iron Overload and Heart Function by CMR In Different Phenotypic Groups of Thalassemia Major Patients
Authors: Dell'Amico Maria Chiara , Meloni Antonella , Filosa Aldo , Rossi Giuseppe , Positano Vincenzo , Favilli Brunella , Marchi Daniele De , Grippo Teodosio , Trunfio Roberto , Maggio Aurelio , Lombardi Massimo , Pepe Alessia 
Published: October 2019

Abstract
Abstract 4264

Introduction.
β-thalassemia major is a genetic disorder characterized by the absence (β°) or reduced output (β+) of the β chains of haemoglobin. This disorder displays a great deal of phenotypic heterogeneity, not fully investigated in terms of cause-effect (Refaldi C et al, Blood Transf 2005; Thein SL, Haematologica 2005). The aim of our study was to detect if different phenotypes could be related to different levels of cardiac impairments, evaluated by cardiovascular magnetic resonance (CMR).

Methods.
We performed a retrospective review of the CMR results and of clinical data about 328 TM patients (age 29 ± 9 years, 52% females) enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) project (Meloni A et al, Int J Med Inform). In the MIOT network all CMR and thalassemia centers are linked by a web-based network, configured to collect patients' anamnestic, clinical, and diagnostic data. Myocardial iron overload was assessed by using a multislice multiecho T2* approach (Pepe A et al, Eur J Haem 2006). Three short axis views (basal, medium, and apical) of the left ventricle (LV) were acquired and analyzed using a custom-written, previous validated software (HIPPO MIOT®). The myocardium was automatically segmented into a 16-segments standardized LV model and the T2* value on each segment was calculated as well as the global T2* value. Cine sequences were obtained to quantify biventricular morphological and functional parameters.

Results.
Three groups of patients were identified: heterozygous (N=172), homozygous β+ (N=58), homozygous β° (N=98). No significant differences for sex and age were found among the groups. The homozygous β+ group showed higher global heart T2* values than the heterozygous and homozygous β° group (32 ± 11 ms vs 26 ± 13 ms vs 23 ± 13 ms, P=0.001) (see figure). The homozygous β+ group showed lower left LV mass index than the heterozygous group (54 ± 10 g/m2 vs 60 ± 14 g/m2, P=0.045). The homozygous β+ group showed higher LV ejection fraction (EF) values than the heterozygous group (64 ± 5 % vs 60 ± 7 %, P&lt;0.0001) and higher right ventricular EF values than the heterozygous and homozygous β° group (64 ± 5 % vs 59 ± 8 % vs 60 ± 7 %, P&lt;0.0001).

Conclusions.
The homozygous β+ TM patients showed less myocardial iron overload and a concordant better global systolic heart function and cardiac remodelling. These data support the knowledge of the different phenotypes in the clinical and instrumental management of the TM patients suggesting stricter monitoring by CMR in homozygous β° TM patients.

Disclosures:
No relevant conflicts of interest to declare.
NK Cell Proliferation and Cytolytic Function Are Compromised In the Hypoxic Tumor Microenvironment
Authors: Ang Sonny , Silva Maria Lima Da , Dawson Margaret , Figliola Matthew , Maiti Sourindra , Huls Helen , Shpall Elizabeth J. , Champlin Richard , Lee Dean A. , Silla Lucia , Cooper Laurence J.N. 
Published: October 2019

Abstract
Abstract 4291
Natural Killer (NK) cells have important and potent innate immunoregulatory and immune surveillance functions against tumor. The paradoxical coexistence of tumors and anti-tumor immune cells (“Hellstrom Paradox”) may in part be explained by the pathophysiology of the “hostile” tumor microenvironment which suppress immune-cell function, such as hypoxia, low pH, low tissue glucose, and the presence of immunosuppressive cytokines and metabolites. However, the effect of the malignant environment on the ability of NK cells to infiltrate tumor and exhibit effector function is largely unknown. Therefore, we investigated the ability of NK cells to operate under conditions of hypoxia. Importantly, NK cells showed a 1,000-fold reduction in proliferative capacity when grown under chronic hypoxia (4 weeks of 1% O2). In addition, there was a corresponding decrease in cytotoxicity as revealed by chromium release assay. This was in contrast to autologous T cells which could numerically expand under corresponding growth conditions. Expression profiling uncovers profound upregulation of hypoxia-inducible genes such as EGLN1(9.9x), EGLN3(52x), LDHA(11.5x), SLC2A1(30.5x), PDK1(16.8x), VEGFA(286x) and BNIP3(138x) in hypoxic NK cells. Protein expression confirmed these changes, as NK cells under normoxic culture produced 520 nmoles/million cells of ATP, while those under hypoxic culture managed only 100 nmoles/million cells. This is consistent with a bioenergetic switch from oxidative phosphorylation to glycosis resulting from PDK1 upregulation. NK cells in hypoxia produced 61 pg/mL of VEGF compared to 1480 pg/mL for NK cells in normoxia (20% O2), as determined by ELISA. The inability of NK cells to propagate under conditions of hypoxia may be due to a drop in mitochondrial content we observed when cells were exposed to chronic hypoxia, a potential mitophagic effects of BNIP3 upregulation. In addition to the poor proliferative capacity of NK cells under hypoxia, we also noted the loss of CD56 expression on hypoxic NK cells which is associated with loss of cytotoxicity. Sequence analysis reveals that miR-210 can bind to the 3′UTR of CD56 mRNA, targeting it for degradation. Therefore, we investigated whether miR-210 levels are upregulated in hypoxic NK cells and found that increased presence correlated with loss of CD56 expression. This leads to the conclusion that NK-cell immunotherapy may be improved by downregulating miR-210 levels. Indeed, our findings help shape strategies for obtaining robust and sustained NK-cell effector function for adoptive immunotherapy in the hypoxic tumor microenvironment.

Disclosures:
No relevant conflicts of interest to declare.