bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cortactin Expression Is Tightly Connected to B-Cell Chronic Lymphocytic Leukemia Aggressiveness
Authors: Gattazzo Cristina , Martini Veronica , Frezzato Federica , Trimarco Valentina , Ave Elisa , Carraro Samuela , Visentin Andrea , Semenzato Gianpietro , Trentin Livio 
Published: October 2019

Abstract
Abstract 4561

Background.
Cortactin is an ubiquitous actin-binding protein, encoded by EMS1 gene and localized in chromosome 11q13 region. This protein is expressed in nearly all mammalian tissues and mostly localizes to dynamic actin structures. As a consequence, cortactin is involved in regulating several actin-dependent processes, including lamellipodium protrusion, trafficking of the key invadopodia proteases and intracellular transducer downstream to kinase-mediated cell signalling upon phosphorylation by Src and Syk tyrosine kinase families. Cortactin is over-expressed in several tumors, such as esophageal squamous cell carcinoma, head and neck squamous cell carcinoma and gastric carcinoma, and so tied to tumor aggressiveness by the promotion of cell invasion and metastasis. We previously showed that cortactin is over-expressed also in neoplastic B cells of patients with B-Cell Chronic Lymphocytic Leukemia (B-CLL). In the present study we investigated the regulation of cortactin activity by the Src kinase Lyn in neoplastic B-CLL cells and the biological implications of cortactin overexpression in this leukemia.

Methods.
Twenty patients and ten normal controls were enrolled. Informed consent was obtained from all patients according to the Declaration of Helsinki. CD19+ lymphocytes were purified from peripheral blood by negative selection using the RosetteSep cells isolation kit (StemCell Technologies). Cortactin localization was performed by Confocal Microscope analysis at basal condition, in presence of the chemotactic stimulus CXCL12 and Src kinase inhibitor PP2. Lyn kinase and cortactin phosphorylation levels were evaluated by western blotting analysis. Migration assay was performed using 3 μm pore filters (Transwell Permeable Supports) in the presence of CXCL12, Src kinase inhibitor PP2 and after cortactin silencing.

Results.
We found that cortactin localization is regulated by Lyn kinase through its phosphorylation. In CLL cells, cortactin was over-phosphorylated and it did not co-localize with actin, as compared to normal cells. PP2-inhibition of Lyn decreased cortactin phosphorylation and triggered its co-localization with actin. Cortactin over-expression proved to be associated to the increased B-CLL spreading through Lyn activity. In fact, not only cortactin over-expression correlated with leukemic cell increased response to CXCL12 (r = 0.9), but also the inhibition of cortactin activity, through PP2 inhibitor or cortactin silencing, drastically reduced neoplastic cell migration after chemotactic triggering.

Conclusions.
These results suggest that cortactin is involved in aggressiveness and spreading of B-CLL cells and that Lyn-cortactin axis could represent an alternative target for the development of new therapeutic strategies.

Disclosures:
No relevant conflicts of interest to declare.
A Splicing Variant of MDM4 Overexpression Plays an Indicator of p53 Aberrations and Marks a Potential Therapeutic Target in Chronic Lymphocytic Leukemia
Authors: Xu Wei , Liu Ling , Fan Lei , Wang Li , Zhang Run , Xu Ji 
Published: October 2019

Abstract
Abstract 4564

Objective
Human homolog of murine double minute 4 (MDM4) belongs to murine double minute (MDM) family. Splicing variant of MDM4 (S-MDM4) is obtained from the deletion of exon 6, which results in an internal deletion of 68 bp. Murine double minute 2 (MDM2) is an analogy of MDM4 and shares highly similar structure with each other. The MDM4 gene plays a crucial role in regulating p53 activity and has been found to overexpress in chronic lymphocytic leukemia (CLL). The purpose of this study was to investigate the prognostic significance of MDM4, and characterize the role of MDM4 in p53 pathway.

Methods
Full-length MDM4 (FL-MDM4), S-MDM4 and MDM2 mRNA expressions were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in 140 Chinese patients with CLL. The correlation between those MDM expressions and CLL prognostic marker such as clinical stage, immunoglobulin heavy-chain variable region (IGHV) mutational status, ZAP-70, CD38, and chromosomal abnormalities were analyzed. Furthermore, primary CLL cells were treated in vitro with either fludarabine or Nutlin-3, to explore the interaction between p53 status and those MDMs.

Results
FL-MDM4 and S-MDM4 expressions were significantly increased with the del(17p13) (P=0.037 and P=0.006), p53 mutations (P=0.023 and P<0.001) and p53 aberrations (P=0.024 and P<0.001). The correlation between the level of MDM2 expression and p53 status was not observed (P=0.196, P=0.095 and P=0.092, respectively). High level of S-MDM4 mRNA expression was associated with short treatment free survival (TFS) (P=0.004). FL-MDM4 expression was significantly decreased after 24 h treatment with fludarabine (P=0.001), but increased after Nutlin-3-treated (P=0.008) in primary CLL cells without p53 aberrations. Both S-MDM4 and MDM2 expressions were significantly increased after fludarabine-treated in CLL cells without p53 aberrations (P=0.013 and P=0.030). Besides, MDM2 overexpression also occurred in CLL cells with p53 wild type after Nutlin-3-treated (P=0.018). In the primary CLL cells with p53 aberrations or p53 dysfunction, the levels of FL-MDM4, S-MDM4 and MDM2 expressions were not significantly increased or decreased after fludarabine or Nutlin-3 treatment.

Conclusion
S-MDM4 overexpression is an indicator of p53 aberrations in CLL patients, suggesting those patients have a poor prognosis. FL-MDM4 inhibitory effect on p53 can be removed by MDM2-p53 and saved by Nutlin-3, and S-MDM4 overexpression marks a potential therapeutic target in CLL.

Disclosures:
No relevant conflicts of interest to declare.
6q Deletion Helps in the Discrimination Between Symptomatic Waldenström's Macroglobulinemia and Asymptomatic Forms of IgM Monoclonal Gammopathies
Authors: García-Sanz Ramón , Magalhaes Roberto JP , Ocio Enrique M , Giraldo Pilar , de las Heras Natalia , Aguilera Carmen , Hernández Jose Mariano , de Coca Alfonso Garcia , Puig Noemi , Murillo Ilda , Sebastian Elena , González Marcos , Miguel Jesus F. San , Gutierrez Norma 
Published: October 2019

Abstract
Abstract 4566
Cytogenetic abnormalities are present in virtually all cases of Waldenström's macroglobulinemia (WM). Among them, deletion of the long arm of chromosome 6 (6q-) is the most frequently reported in the literature, but the potential impact on disease evolution has not been completely elucidated. In this study we have analyzed the prevalence of this aberration in 203 patients with B-cell lymphoproliferative disorders (B-LPD) producing a monoclonal IgM component. Detection was evaluated by In Situ Fluorescence Hybridization in CD19+ separated cells and results were correlated with disease characteristics. The frequency of 6q21 deletion varied according to the type of B-LPD: 1/42 (2%) in IgM-MGUS, 5/69 (7%) in asymptomatic WM (aWM), 25/83 (30%) in symptomatic WM (sWM) and 0/9 in other IgM B-LPD. Within MGUS and aWM, patients with deletion of 6q displayed a high frequency of adverse prognostic features and required treatment earlier than patients with normal 6q (37 mo vs. +120 mo, p<0.05) although they finally displayed a similar overall survival. Within the sWM, those patients with del(6q) displayed parameters of high tumor burden, such as high levels of b2M and monoclonal paraprotein and more frequent anemia and hypoalbuminemia. Interestingly, there was a correlation between the presence of 6q deletion and the ISS prognostic index (frequency of 6q- among patients stratified in stages 1, 2 and 3 was 24%, 42% and 67% respectively). However, overall survival analysis did not show any difference between patients with and without 6q-, independently if the overall survival was considered globally or free of specific disease mortality. In summary, in IgM monoclonal gammopathies, 6q deletion is associated with more symptomatic forms, higher probability of treatment requirement and high tumor load, although the presence of this abnormality does not represent necessarily an adverse prognosis for OS.

Disclosures:
Ocio: PharmaMar: Patents & Royalties, Research Funding. San Miguel:Celgene: Honoraria; Millenium: Honoraria; Janssen: Honoraria.
Menorrhagia in Women with Severe Bleeding Disorders
Authors: Halimeh Susan , Davies Joanna , Pollard Debra , Abdul-Kadir Rezan 
Published: October 2019

Abstract
Abstract 4626
The management of menorrhagia presents a challenge in women with severe bleeding disorders. Conservative medical management is the first line treatment and most women with severe bleeding disorder require combination treatment. Surgical intervention may ultimately be offered to women in whom medical management has failed and whom no longer desire fertility. Women with low factor levels are at risk of perioperative bleeding complications and may require haemostatic support. A total of 50 women with severe factor deficiencies (less than 20iu/dL) were included in this study. 46 women were registered at the Haemophilia Centre at the Royal Free Hospital in London. Four cases were also included from the Rhine-Ruhr Haemophilia Centre in Duisburg, Germany. We reviewed the occurrence of menorrhagia and the management options that were offered. In those that required surgical intervention, the incidence of postoperative bleeding complications and the requirement for factor concentration was also reviewed.
The bleeding disorders in these women were 34 (68%) with severe factor XI deficiency, 10 (20%) with severe type 1 and type 3 von Willebrand's disease, 4 (8%) with factor VII deficiency, 2 (4%) had factor V or X deficiencies and one (2%) had a combination of factor VI and VIII deficiency. The ISTH/SSC joint working group bleeding assessment tool was used to assess the severity and frequency of bleeding symptoms among this cohort of women. The bleeding scores ranged from −2 to 30 with a median score of 9.5.
In total, 32 out of 50 (64%) women with severe factor deficiency required medical attention for menorrhagia. Medical treatment included hormonal preparations (combined oral contraceptive pill or levonorgestrel intrauterine device), which was used as a first line treatment in 15 out of 32 (46.8%) women. Haemostatic treatment included antifibrinolytic medication such as tranexamic acid, which was used in combination with hormonal therapy. One women required intranasal DDAVP, von Willebrand factor concentrate and tranexamic acid. Failure to control menstrual bleeding occurred in 14 (43.7%) women and surgical intervention was required. 7 out of 14 (50%) women required hysterectomy and the remaining 7 women underwent endometrial ablation. Prophylaxis with factor concentration to cover surgical intervention was given in 8 out of 14 women (64.2%). The remainder received tranexamic acid for 24–48 hours following surgery. Postoperative bleeding occurred in 7 women that had surgical intervention, despite two women receiving prophylaxis. This study highlights the complexity involved in the management of menorrhagia in women with severe bleeding disorders and the high risk of postoperative bleeding.

Disclosures:
No relevant conflicts of interest to declare.
The Ratio of Treg/Th17 Cells Correlates with the Platelet Number in Different Disease State of Primary Immune Thrombocytopenia
Authors: Ji Lili , Li Feng , Zhan Yanxia , Hua Fanli , Zou Shanhua , Wang Weiguang , Cheng Yunfeng 
Published: October 2019

Abstract
Abstract 4649

Background:
Primary immune thrombocytopenia (ITP) is an autoimmune heterogeneous disorder that is characterized by decreased platelet count. Regulatory T (Treg) cells and T helper type 17 (Th17) cells are two subtypes of CD4+T helper (Th) cells. They play opposite roles in immune tolerance and autoimmune diseases, while they share a common differentiation pathway. The imbalance of Treg/Th17 has been demonstrated in several autoimmune diseases. In this study, we aimed to investigate the ratio of the number of Tregs to the number of Th17 cells in ITP patients and evaluate the clinical implications of the alterations in this ratio.

Methods:
Thirty adult patients with newly diagnosed ITP enrolled in this study. Patients who needed treatment had been clinically followed up for 12 months. The percentages of CD4+CD25hiFoxp3+ Treg cells and CD3+CD4+IL-17-producing Th17 cells in these patients and healthy controls (n=17) were longitudinally analyzed by flow cytometry.

Results:
The percentage of Treg cells in ITP patients was significantly lower than that of healthy controls and the percentage of Th17 cells increased significantly at disease onset. It is suggested that the ratio of Treg/Th17 correlated with the disease activity.

Conclusion:
The ratio of Treg/Th17 might be relevant to the clinical diversity of ITP patients, and this Treg/Th17 ratio might have prognostic role in ITP patients.

Disclosures:
No relevant conflicts of interest to declare.
Thrombopoietin Receptor Agonist (ELTROMBOPAG) for Chronic Immune Thrombocytopenic Purpura (ITP) Treatment: 21 Patients in Only One Center
Authors: Román Teresa Álvarez , Salces Monica Martin , Butta Nora V. , Canales Miguel , Fernandez Ihosvany , de la Rua Ana , Yuste Victor Jimenez 
Published: October 2019

Abstract
Abstract 4658

Introduction
ITP management has changed since thrombopoietin receptor agonists (TRAs) were approved for its treatment. Current TRAs are recommended for adults at risk of bleeding who relapse after splenectomy, as well as for those where splenectomy is contraindicated and where, at least, one other therapy has failed.
The goal of this paper is to present the results of the treatment and follow-up of 21 patients treated with Eltrombopag in our Centre during the last year.

Patients
We present 21 patients diagnosed with chronic ITP according to the American Society of Hematology guidelines. 7 of them were males and 14 females. The median age was 70 years (range from 26 to 81 years). Previous splenectomy was undergone in 3 patients. 10 patients had previously received two or more therapies for ITP. 11 patients received TRAs as second line treatment.

Results
On average, platelet counts at the beginning of the treatment with Eltrombopag were 23.000/μL. All patients started with the same doses (50 mg) except one of them who started with 25 mg. Patients only received concurrent ITP therapy (corticosteroids and intravenous immunoglobulins) when platelet counts were under 20,000/μL or bleeding occurred.
8 patients needed rescue medications throughout the treatment with Eltrombopag (7 of them only once). Eltrombopag was withdrawn in a total number of 8 patients due to different reasons: 4 patients were considered as non-responders (3 of them didn't achieve a certain platelet count to prevent major bleeding and, in the fourth one, reducing or suspending the concurrent ITP therapy was not possible. One of these non-responders received Romiplostin and a good response was achieved). In one patient, the therapy was withdrawn due to liver toxicity and in another one, at patient's request. Finally, Eltrombopag was withdrawn in 2 patients because a sustained platelet counts was held.

Conclusion
TRAs are safe, effective and well-tolerated for those patients who relapse after splenectomy or when splenectomy is contraindicated. In our experience, TRAs could be also useful in other diseases like HCV or HIV associated thrombocytopenia. Eltrombopag and Romiplostin bind in different places to the TPO receptor (TPO-R). This circumstance, together with the different activation pathways, may explain that some non-responders to Eltrombopag could respond to Romiplostin and viceversa.

Disclosures:
No relevant conflicts of interest to declare.
Chemokine Receptor Expression, Migration, and Survival of NK Cells Expanded with Mbil-15 or Mbil-21
Authors: Lee Dean , Aliru Maureen , Denman Cecele J. , Somanchi Srinivas S. 
Published: October 2019

Abstract
Abstract 4683
Natural killer (NK) cells can kill malignant or virus-infected cells through the interaction of activating and inhibitory receptors without needing specific antigen recognition of target cells, and therefor have broad therapeutic applications for treatment of human malignancies. However, due to their limited life-span in vivo and poor expansion in vitro, production of sufficient numbers of NK cells for effective adoptive immunotherapy poses an obstacle. Genetically engineered artificial antigen presenting cells (aAPCs) consisting of K562 modified 4-1BBL and membrane bound IL-15 or IL-21 have been reported for their ability to support ex vivo NK cell proliferation. aAPCs with mbIL-21 were shown to promote increased proliferation of NK cells with shorter telomeres, but differences in in vivo survival or tumor or tissue migration have not been assessed. Tumor and/or tissue migration is primarily mediated by the expression of chemokine receptors. Using aAPCs bearing mbIL15 or mbIL21, we expanded NK cells for 3 weeks and assessed their expression of chemokine receptors, organ migration, and in vivo survival in a xenograft model. Propagated NK cells showed relatively similar levels of low to modest expression of CCR2, CCR7, CXCR4 and CXCR5, and high expression levels of CXCR3. Mean CCR5 expression levels were similar on cells that were positive, but CCR5 was expressed on a higher percentage of NK cells expanded with mbIL-15 than those expanded with mbIL-21. In contrast, about 20% of mbIL-21 expanded NK cells expressed CX3CR1 expression whereas mbIL-15 NK cells showed almost no expression of this receptor. Results from ongoing migration and survival experiments will also be presented.

Disclosures:
No relevant conflicts of interest to declare.
Different Strategies for First-Line Treatment of Chronic Myeloid Leukaemia: An Economic Analysis
Authors: Wu Bin , Zhong Hua , Saglio Giuseppe , Chen Fangyuan 
Published: October 2019

Abstract
Abstract 4696

Purpose:
To evaluate the economic outcome of conventional and targeted therapies of patients with chronic myelogenous leukemia (CML).

Methods:
Two Markov simulation models were designed to measure the cost and quality-adjusted life years (QALYs) for newly diagnosed CML patients whether to be administered conventional therapy or six tyrosine kinase inhibitors (TKIs) based strategies. Clinical and utility data were taken mostly from the literature by a MEDLINE search. Costs were based on local charges. The primary output was reported in terms of incremental cost-effectiveness ratios (ICERs). Sensitivity analyses were performed to examine the robustness of the model output. The impact of patient assistance program (PAP) was assessed.

Results:
The imatinib plus peginterferon-Á switch 2nd TKIs strategy yielded the most health benefits for newly diagnosed CML patients when compared with the conventional, imatinib switch 2nd TKIs, imatinib switch conventional, imatinib plus IFN-Á switch conventional, nilotinib switch conventional and dasatinib switch conventional strategies (figure 1). Marginal cost-effectiveness was $79,134 or $17,600 per QALY gained relative to conventional strategy without or with PAP (figure 2). Both the nilotinib and dasatinib based strategies were more expensive yet less effective than the alternative strategies and were therefore dominated. Model outputs were sensitive to the cost of TKIs.

Conclusion:
Imatinib and imatinib plus peginterferon-Á based strategies are potentially more cost-effective and 2nd-generation TKIs may be preferred in the setting of imatinib failure. Patient assistant program in health resource limited setting might notably improve the economic outcome of TKIs based therapies.

Disclosures:
No relevant conflicts of interest to declare.
Use of the Functional Assessment of Cancer Therapy-Anemia (FACT-An) Instrument in Persons with MPN-Associated Myelofibrosis and Anemia
Authors: Hudgens Stacie , Tencer Tom , Gale Robert Peter Peter , Khan Zeba M. 
Published: October 2019

Abstract
Abstract 4706

Background.
Myeloproliferative neoplasm (MPN)-associated myelofibrosis is characterized by anemia in almost all affected persons. The Functional Assessment of Cancer Therapy (FACT) measurement system is a patient-reported outcome (PRO) developed to document symptoms to diverse aspects of cancer treatment. One FACT version, FACT-An, specifically addresses symptoms of anemia related to cancer- therapy. FACT-An has been validated in diverse cancer populations but not in MPN-associated myelofibrosis.

Methods.
Data were from a phase-2 randomized double-blind Bayesian “pick-the-winner” trial of pomalidomide and prednisone in subjects with MPN-associated myelofibrosis and anemia (including RBC-transfusion-dependence). Details of the study, including definitions of anemia, response, RBC-transfusion-dependence and –independence were published previously. Change in quality of life (QOL) from randomization to the last cycle of therapy was evaluated by using the FACT-An physical well-being (PWB), functional well-being (FWB), trial outcome index (TOI) and anemia (An) domains. Minimally clinically important differences (MID) were used to determine the smallest difference in scores which subjects perceived as beneficial in the FACT-An domains of interest. Subjects were classified as meeting MID for responsiveness if their change score from baseline was greater than one standard error of measurement (SEM), indicating improvement.

Results.
85 subjects were studied. All FACT-An domains showed strong reliability as measured by Cronbach's alpha. 31 were classified as anemia responders by clinical and laboratory criteria. Anemia responders showed greater improvement in PWB, FWB and TOI scores than non-responders (TOI presented below) across all FACT-An domains. Improvement began at the 2nd 28 d cycle of therapy and was sustained.

Conclusion.
We show anemia response defined by IWG-MRT criteria correlates with improved QOL measured by the FACT-An instrument in persons with MPN-associated myelofibrosis.

Disclosures:
Tencer: Celgene Corporation: Employment. Gale:Celgene Corporation: Employment. Khan:Celgene: Employment.