bluuebunny/crossref_metadata_2025_split huggingface dataset:
MYC Functions As a Master Switch for Natural Killer Cell-Mediated Immune Surveillance of Lymphoid Malignancies
Authors: Swaminathan Srividya , Heftdal Line Dam , Liefwalker Daniel F , Dhanasekaran Renumathy , Deutzmann Anja , Horton Crista , Mosley Adriane , Liebersbach Mariola , Maecker Holden T. , Felsher Dean 
Published: October 2019

Abstract
Background: The MYC oncogene drives T and B cell lymphoid malignancies, including Burkitt's lymphoma (BL) and Acute Lymphoblastic Leukemia (ALL). Such lymphomas are said to be "oncogene-addicted" to MYC. In order to develop targeted therapies for MYC-driven cancers, it is vital to understand how MYC regulates both cell autonomous and non-cell-autonomous processes, including host immunity.
Approach: We have used a particularly tractable approach for studying the role of oncogenic MYC on the host immune system during lymphomagenesis through a tetracycline (tet)-system regulated transgenic mouse model of MYC-driven T cell lymphoma (SRα-tTA/Tet-O-MYC mice; Felsher and Bishop, Molecular Cell, 1999). By delineating the global immunological changes during primary MYC-driven T cell lymphomagenesis in SRα-tTA/Tet-O-MYC mice using mass cytometry (CyTOF) and CIBERSORT, we identified anti-tumor immune subsets that can be developed as therapies to treat MYC-driven lymphomas.
Results: Amongst the immune subsets evaluated, our results demonstrated a specific systemic suppression of natural killer (NK) cell-mediated surveillance in SRα-tTA/Tet-O-MYC mice bearing overt MYC-driven T cell lymphomas. Inactivation of lymphoma-intrinsic MYC restores NK cell-mediated immune surveillance, suggesting that the regulation of NK cell-mediated surveillance may be integral to MYC-induced lymphomagenesis. We observed that lymphoma-specific MYC transcriptionally represses STAT1/2 and secretion of Type I Interferons (IFNs) required for normal NK cell homeostasis and NK cell-mediated immune surveillance in the tumor microenvironment. Concordantly, treating T cell lymphoma-bearing SRα-tTA/Tet-O-MYC mice with Type I IFN improves survival by rescuing NK cell production, and in part overriding MYC-mediated suppression of NK surveillance. We showed that human lymphomas with both high levels of MYC and low levels of STAT1/2 have lower NK surveillance, and are associated with poor prognosis. Finally, we established the therapeutic implications of our findings by showing that adoptive transfer of NK cells significantly delays lymphoma initiation, and recurrence after MYC inactivation; suggesting that NK cell-based therapy may be effective against MYC-driven lymphomas.
Conclusion: Subversion of NK cell surveillance is integral to MYC-induced lymphomagenesis. Our studies provide a rationale for further developing the NK subset as a cell-based immunotherapy to effectively treat MYC-driven lymphomas in the future.

Disclosures
No relevant conflicts of interest to declare.
Promising Effect of PDL1 Inhibitors in PCNSL
Authors: Hamed Rasha , Alshemmari Salem , Hamadah Abdulaziz , ElHagrasy Rehab S , Shaisha Mohamed Elbialy , Seif Marwa 
Published: October 2019

Abstract
PCNSL or secondary CNSL both are associated with poor prognosis & inferior survival, and some cases are refractory to currently available lines of treatment. PDL1 inhibitors started to emerge in the literature as a new line of treatment in this disease entity. The programmed death ligand PD-L1 negatively regulate immune response & promote escape of tumor cells from immune surveillance, PD1 is expressed on T lymphocytes, including tumor infiltrating lymphocytes (TILs), while PDL1 expression is found on antigen presenting cells & on tumor cells in various cancer types, including some lymphomas. Binding of PDL1 to PD1 inhibits the proliferation of activated T lymphocytes & thus the anti-tumor adaptive immune response. In this case we evaluated the effect of PDL1 inhibitor Nivolumab in PCNSL refractory to 1st line (high dose MTX/AraC-Rituximab). Efficacy was evaluated using MRI which showed complete remission following 4 bi-weekly cycles, maintained complete remission on repeated evaluation after 10th & 14th cycles. The patient was shifted to monthly doses. The patient tolerated the treatment well apart of mild elevation of trans-aminases. Time to treatment failure was not reached till time of submission of this abstract (8 months). PDL1 Inhibitors showed effective clinical and radiological response in PCNSL. Further studies are needed to assess this point and follow up to assess the time to treatment failure. The remaining un-answered question is: How to consolidate the achieved response?
Figure. Figure.

Disclosures
No relevant conflicts of interest to declare.
Parallel Evaluation of Three Global Hemostatic Assays in Response to Factor VIII Inhibitors
Authors: Chen Ping , Jani Jayesh , Zheng Gang , Kickler Thomas S. 
Published: October 2019

Abstract
Background Current laboratory tests measuring factor and factor inhibitor levels are limited in their ability to fully evaluate the hemostasis status of hemophilia patients. There are global assays including thromboelastogragh (TEG), Innovance ETP, and thrombinoscope measuring thrombin generation potential, which have potentials to provide more objective and clinically relevant markers to guide clinical management. However, performance characteristics of these global assays are not well-studied, and no parallel comparisons of three global assays have been made.
Material and Methods With plasmas of 20 healthy individuals the normal variation of thrombin generation potential was determined for all three global assays. With five commercially available and three clinical plasma samples with different levels of factor VIII inhibitors, serial dilutions were made, and thrombin generation potentials were measured with the global assays.
Results The means and standard deviations for thrombin generation potential of healthy individuals are 761.27±70.30 mm/min, 2126.43±441.62 nM/min, and 411.04±48.87 mA, by TEG, throminoscope and Innovance ETP respectively. Thrombinoscope shows a dose-dependent response to different levels of factor VIII inhibitors from the same patients, while Innovance ETP shows virtually no response to factor 8 inhibitors regardless of inhibitor levels. TEG appears more sensitive to factor VIII inhibitors than thrombinoscope, as a moderate level of factor VIII often abolishes thrombin generation by TEG (see Figure 1 for an example). Importantly, it was shown that the same levels of factor VIII inhibitor from different patients result in different level of inhibition for thrombin generation potential by thrombinoscope (Figure 2), which potentially explains the phenotypic heterogeneity of patients with same levels of factor VIII inhibition.
Conclusion Global assays like thrombinoscope, but not Innovance ETP, offer an objective measurement of hemostasis in hemophilia patients with factor VIII inhibitors, which may lead to individualized hemophilia patient management. Future studies are warranted to validate the global assays clinically.

Disclosures
No relevant conflicts of interest to declare.
Regulating Transcriptional Co-Activator PGC-1α for the Treatment of Sickle Cell Disease
Authors: Habara Alawi , LE Cuong , Murphy George J , Chui David H.K. , Steinberg Martin H. , Cui Shuaiying 
Published: October 2019

Abstract
Sickle cell disease (SCD) is the most common inherited human hematologic disease, which causes hemolytic anemia, pain, disability, progressive multi-organ damage and early mortality. Clinical studies have shown that increased synthesis of fetal hemoglobin (HbF) in sickled erythroid cells leads to diminished severity of many clinical features of SCD. Therefore, therapeutic agents that can increase HbF production will be of benefit to SCD patients. Hydroxyurea (HU) is the FDA-approved therapeutic for treatment of SCD, but not all patients respond favorably or adequately. Therefore, other methods of targeting HbF are highly desired, particularly those that act by different mechanisms that might be used in combination with HU or alone (for those who do not tolerate HU).
We recently identified PPARγ co-activator (PGC-1α) as a new protein involved in the regulation of the fetal globin genes. Forced overexpression of PGC-1α in vitro by adenovirus infection in bone marrow cells from SCD mice resulted in significantly increased human γ- and murine εy- and βh1-globin genes. Furthermore, up-regulation of PGC-1α by a small molecular agonist (Compound Z) in human umbilical cord blood-derived erythroid progenitor (HUDEP-1) cells markedly increases γ-globin gene expression and HbF synthesis. The highest response was achieved when HUDEP-1 cells were treated with 5µM Compound Z for 2 days, which results in 66.6% HbF+ cells compared to vehicle control (29.5% HbF+ cells). The effect of Compound Z in inducing HbF was further validated in erythroblasts derived from cultures of normal adults' CD34+ cells as well as in iPSC-derived sickle erythroblasts (SS24 cells). These data suggest that modulating PGC-1α activity may be effectively applied to the treatment of SCD since enhanced HbF synthesis would alleviate pathophysiological effects of SCD.

Disclosures
No relevant conflicts of interest to declare.
Preclinical Evaluation for the Gene Therapy of Patients with Leukocyte Adhesion Deficiency Type I
Authors: Almarza Elena , Mesa-Núñez Cristina , Damián Carlos , Fernández-García María , Díez-Cabezas Begoña , Schwartz Jonathan D , Bueren Juan A 
Published: October 2019

Abstract
Leukocyte Adhesion Deficiency Type I (LAD-I) is a severe primary immunodeficiency characterized by recurrent and life-threatening bacterial infections. It is caused by mutations in the ITGB2 gene, encoding the integrin β2 common subunit (CD18). These mutations lead to defective or absent expression of β2 integrins on leukocyte surfaces, rendering leukocytes unable to extravasate to infection sites. Severe LAD-I is characterized by less than 2% of normal CD18 neutrophil expression and is fatal during the initial 2 years of life in 60-75% of patients in the absence of allogeneic hematopoietic transplant. As it is the case with other monogenic immunodeficiencies, LAD-I is a disorder that could be corrected by ex vivo gene therapy. To this aim we have developed a lentiviral vector (LV) that has recently obtained the Orphan Drug designation (EU/3/16/1753 and DRU-2016-5430). In this LV the expression of hCD18 is driven by a chimeric promoter with a higher activity in myeloid cells. Comprehensive safety and efficacy preclinical LV-mediated gene therapy studies have been conducted in LAD-I mouse models harboring either hypomorphic or knock-out mutations in the ITGB2 gene. Our studies demonstrate stable engraftment of gene corrected LAD-I mouse hematopoietic stem cells in LAD-I recipients and indicate a phenotypic correction of peripheral blood neutrophils. A complete preclinical safety evaluation of the vector was also carried out demonstrating the absence of hematotoxic and genotoxic effects in treated animals. Further studies have been conducted with GMP-produced LVs in human CD34+ cells aimed at optimization of cell transduction. The use of transduction enhancers (TEs) significantly improved the efficacy of genetic correction of human CD34+ cells transduced with LVs at low MOIs. Additionally, transplants into immunodeficient mice showed no changes in the repopulating ability of CD34+ cells when these cells were transduced in the presence of TEs. As occurred in in vitro cultures, significant increases in the transduction of repopulating cells were also associated with the use of TEs, indicating that optimized TE combinations will enable practical and cost-effective transduction of human HSCs in gene therapy protocols. Taken together, these results demonstrate the efficacy and safety of a gene therapy approach directed towards the therapy of LAD-I patients.

Disclosures
Almarza: Rocket Pharmaceuticals: Equity Ownership, Patents & Royalties, Research Funding. Schwartz:Rocket Pharmaceuticals: Employment, Equity Ownership. Bueren:Rocket Pharmaceuticals: Consultancy, Equity Ownership, Patents & Royalties, Research Funding.
Erythroferrone Inhibits the Induction of Hepcidin By BMP6
Authors: Arezes Joao , Foy Niall , McHugh Kirsty , Sawant Anagha , Benard Susan , Quinkert Doris , Terraube Virginie , Brinth Alette , Tam May , LaVallie Edward , Taylor Stephen , Armitage Andrew E , Pasricha Sant-Rayn , Cunningham Orla , Lambert Matthew , Draper Simon J , Jasuja Reema , Drakesmith Alexander 
Published: October 2019

Abstract
Decreased hepcidin mobilizes iron, which facilitates erythropoiesis, but excess iron is pathogenic in beta-thalassemia and other iron-loading anaemias. Erythropoietin (EPO) enhances erythroferrone (ERFE) synthesis by erythroblasts, and ERFE suppresses hepatic hepcidin production, through an unknown mechanism. The BMP/SMAD pathway in the liver is critical for control of hepcidin, and we show that EPO suppressed hepcidin and other BMP target genes in vivo in a partially ERFE-dependent manner. Furthermore, recombinant ERFE suppressed the hepatic BMP/SMAD pathway independently of changes in serum and liver iron, and in vitro, ERFE decreased SMAD 1/5/8 phosphorylation and inhibited expression of BMP target genes in hepatoma cells. ERFE specifically abrogated the induction of hepcidin by BMP5, BMP6 and BMP7, but had no or very little effect on hepcidin induction by BMP2, 4, 9 or Activin B. A neutralising anti-ERFE antibody prevented the ability of ERFE to inhibit hepcidin induction by BMP5, 6 and 7. Cell-free Homogeneous Time Resolved Fluorescence assays showed that BMP5, BMP6 and BMP7 competed with anti-ERFE for binding to ERFE. Biacore analysis showed that ERFE binds to BMP6 with a higher affinity compared to its binding to BMP2, BMP4 or Activin B, and does not bind to GDF15. We propose that ERFE suppresses hepcidin by inhibiting hepatic BMP/SMAD signaling via preferentially binding and impairing the function of an evolutionarily closely related BMP sub-group consisting of BMP5, BMP6 and BMP7. These findings indicate that ERFE can act as a natural ligand trap generated by stimulated erythropoiesis in order to regulate availability of iron.

Disclosures
Arezes: Pfizer: Research Funding. Foy:Pfizer: Employment. McHugh:Pfizer: Research Funding. Sawant:Pfizer: Employment. Benard:Pfizer: Employment. Quinkert:Pfizer: Research Funding. Terraube:Pfizer: Employment. Brinth:Pfizer: Employment. Tam:Pfizer: Employment. LaVallie:Pfizer: Employment. Cunningham:Pfizer: Employment. Lambert:Pfizer: Employment. Draper:Pfizer: Research Funding. Jasuja:Pfizer: Employment. Drakesmith:La Jolla Pharmaceutical Company: Research Funding; Pfizer: Research Funding; Alnylam: Consultancy; Kymab: Membership on an entity's Board of Directors or advisory committees.
Cost Consideration of Second Line Therapy for Relapsed Diffuse Large Lymphoma in the Community Setting
Authors: Landau Danny , Wilds Brandon , Mouslly Sammy 
Published: October 2019

Abstract
Cost consideration of second line therapy for relapsed diffuse large lymphoma in the community setting
Introduction
Despite treatment with curative intent chemotherapy, many patient with diffuse large B cell lymphoma (DLBCL) will relapse. Post relapse, the majority of patients will remain sensitive to cytotoxic chemotherapy. Commonly used regiments in this situation include Rituximab plus a combination of other agents such asifosfamide, carboplatin, etoposide (R-ICE)etoposide, methylprednisolone, cytarabine, cisplatin (R-ESHAP)dexamethasone, high-dose cytarabine, cisplatin (R-DHAP)gemcitabine, oxaliplatin (R-Gem/Ox)lenalidomide (R squared)bendamustine (R-Bendamustine
As few clinical trials exist that compare these different regimens head to head, the decision is often left to the treating physician. We opted to look at cost as a consideration.
Methods:
For the regimens listed above, we calculated drug costs using the average wholesale price. For regimens that require inpatient hospital stays, we used historical data for cost of average hospital stay from Beckers Hospital review. A body surface area of 1.75 was used for each regimen. We determined the cost for four cycles of the different regimens. Growth factor support was included as many of these regimens require this. As our focus was on our own community institution, and is it isn't yet widely available, CAR-T was not included.
Results:
In table
Conclusions:
While a number of decisions will factor into the use of one of these regimens, cost is an important factor. Based on the above information, there is a wide range of cost. This can be one factor in deciding which combination to use. Few clinical trials have compared these regimens in a head to head fashion. One trial that did compared R-ICE to R-DHAP and essentially showed only minor outcome differences between them. In such situations, cost as well as inpatient vs outpatient hospital stays, patient preference, physician comfort with the different regimens will all play a role in determining which regimen to use.
Table. Table.

Disclosures
Landau: celgene: Honoraria; novartis: Honoraria.
Prevalence of Severe Bacterial Infection in Febrile Children with Sickle CELL Disease in the Era of Pneumococcal Conjugate Vaccine 13
Authors: Contreras-Yametti Gloria , Haidee Custodio , Imran Hamayun 
Published: October 2019

Abstract
Introduction
The incidence of invasive pneumococcal infections in patients with sickle cell disease (SCD) decreased after introduction of penicillin prophylaxis and pneumococcal conjugate vaccine (PCV). However, the decrease in pneumococcal infections alone may not necessarily mean an overall decrease in severe bacterial infections (SBI). In a previous publication, we reported a 0.4 % prevalence of pneumococcal bacteremia following introduction of PCV 13. In the current study, we aimed to define the prevalence of SBI and hospitalization in febrile patients in the same cohort in the later years.
Methods
We performed a retrospective study of patients with SCD <18 years old presenting with fever to University of South Alabama Children's and Women's Hospital from January 2014 to June 2017. SBI was defined as: bacteremia, pneumonia, pyelonephritis, meningitis, osteomyelitis and abscess (superficial and deep). Univariate analysis and multivariate logistic regression were used to determine factors associated with patient disposition as well as presence of SBI.
Results
There were 258 febrile events in 120 patients resulting in 187 (72%) admissions (figure 1). SBI was seen in 12% of admissions with uncomplicated community acquired pneumonia being the most common. The prevalence of bacteremia was 1.6% with single cases of pneumococcus, E. coli, and H. influenzae bacteremia. Younger age, high fever, and splenectomy were associated with hospitalization (p<0.05). However, only C reactive protein was associated with SBI (p<0.02). Viral infection was diagnosed in 80% of outpatients but 87% were given antibiotics. Among inpatients, all received parenteral antibiotics, and 67% were assessed to have viral illness, although only 23% had a virus identified. Pneumococcal vaccination status was satisfactory in 77% of our sample while compliance rate with penicillin prophylaxis was >85% in both inpatient and outpatient groups.
Conclusion
Although majority of febrile events were due to viral infections, 3 of four febrile episodes in our cohort resulted in hospitalization. A small proportion of patients had SBI and a much smaller proportion had bacteremia. These findings support early virus identification which can have implications on patient discharge disposition and antibiotic use. Further studies looking at risk stratification of febrile patients with SCD are needed to encourage outpatient management without compromising safety.
Figure 1. Figure 1.

Disclosures
Imran: Novo Nordask: Speakers Bureau.
Outpatient Fractionated ICE Protocol in Relapsed/Refractory Lymphomas: Efficacy and Safety
Authors: Dada Reyad , Nawaz Azhar , Abdelghany Ehab Mosaad , Boubakra Tarek 
Published: October 2019

Abstract
Objectives: The diagnosis of cancer significantly affects quality of life (QoL) of patients. Admission on wards and spending several days far from home to receive chemotherapy, especially in young patients with Hodgkin lymphoma (HL), might negatively affect the QoL. Therefore, we are offering our patients with relapsed and refractory lymphomas receiving the so-called outpatient fractionated regimen of ifosfamide, carboplatin and etoposide (ICE) as salvage treatment prior to high dose chemotherapy and autologous stem cell transplantation (ASCT).
Methods: We retrospectively collected the data of patients who received outpatient fractionated ICE between 2011-2017 at a tertiary care center. The ICE protocol consisted of: ifosfamide 1500 mg/m2 infused over 2 h daily on days 1-3, carboplatin (mg dose = 5 · AUC) i.v. on day 1, and etoposide 100 mg/m2 i.v. daily on days 1-3, plus filgrastim 5 ug/kg/day s.c. for 5 days. Rituximab 375 mg/m2 on day 1 was added for patients with CD20 positive B cell Non-Hodgkin lymphoma. The Cycles of outpatient ICE were given every 21 days.
Results: 89 patients (44% female and 56% male) with median age of 34 years (17-72) fulfilled the inclusion criteria. Majority of patients had HL (64%). 88% had stage III and IV with 60% having B symptoms and 38% extranodal disease prior to ICE. 5% had transformed lymphoma. Mean of received ICE was 2.5 cycles. The complete remission and partial remission rates for primary refractory (63%) and non-primary refractory (37%) disease were 7% and 25% versus 19% and 38% respectively. Of patients who achieved a response qualifying for ASCT, stem cells were successfully collected with filgrastim alone and plerixafor plus filgrastim in 77.1% and 22.9% respectively. The median of collected stem cells was 6.13 106/kg with mean apheresis of two days. 75% of eligible patients proceeded to ASCT. The relapse free survival rate was 45 months (95% CI 10-80) and overall survival rate 58 months (95% CI 32-84). Mean follow-up time was 33.1 months (range 8-92).
The rate of hematological toxicities grade 3 were documented in 15% with 10% neutropenia and 9% thrombocytopenia. Febrile neutropenia rate was 5.6%. Non-hematological toxicities included oral mucositis 3%, vomiting and diarrhea each 1%. No grade 4 or serious adverse events were observed.
Conclusions: Our institutional experience is, to our knowledge, the largest of it is kind, which showed the outpatient fractionated ICE as an interesting alternative to the classic ICE regimen with favorable safety profile. However, for patients with primary refractory lymphomas more effective regimens are urgently needed.

Disclosures
No relevant conflicts of interest to declare.