bluuebunny/crossref_metadata_2025_split huggingface dataset:
FVIII Specific Memory B Lymphocytes in Hemophilia A with Inhibitors Treated by Immune Tolerance Induction.
Authors: Diaz Isabelle , Bollore Karine , Rothschild Chantal , Chambost Hervé , Claeyssens Ségolène , Tuaillon Edouard , Lapalud Priscilla , Schved Jean-François , Vendrell Jean-Pierre , Lavigne-Lissalde Géraldine 
Published: October 2019

Abstract
Abstract 3162
Poster Board III-99

Background and objectives
Hemophilia A (HA) is a life-threatening hemorrhagic bleeding disorder caused by deficiency of Factor VIII (FVIII). Twenty to thirty percent of HA patients treated by FVIII develop inhibitors. The presence of these inhibitors in high titer (>5 Bethesda Units (BU)/ml) requires modification of the treatment regimen: use of products that by-pass the action of FVIII for haemorrhagic accidents and treatment protocols by immune tolerance induction (ITI) to eradicate inhibitors. The aim of our study was to enumerate and characterize FVIII-specific memory B-cells in peripheral blood by using polyclonal activation of enriched B-cells and an ELISpot assay in hemophilia patients with inhibitors.

Methods
Two groups of patients were prospectively included. First group included six severe HA patients treated by ITI; three with inhibitors (mean 3.04 ± 0.67 BU/ml; mean 14.6±4.2 years old) while the three others had a past of inhibitors, successfully treated by ITI (<0.6BU/ml; mean 18.6 ±6.3 years old). Second group were six severe HA who never developed inhibitors (mean 19.5±1.7 years old). Circulating FVIII specific memory B-cells were enumerated in each cohort and 13 controls using the ELISpot system as previously described. The results were expressed as the number of FVIII specific Secreting Cells (SCs) (IgG, IgA or IgM)/106 B-cells.

Results
In the first group,circulating FVIII-specific IgM-SCs were detected in 5 patients (1.07-45/106 B-cells), FVIII-specific IgA-SCs in 6 patients ( 2.9-7.5/106 B-cells).Only in patients with detectable inhibitors, FVIII-specific IgG-SCs (4-5.2/106 B-cells) were detected. In the second group FVIII-specific IgM-SCs (between 5 and 52 per 106 B-cells) were found, one patient had FVIII-specific IgA-SCs (2/106 B-cells).

Conclusion
We were able to detect FVIII specific memory B-cells. Before the treatment by ITI, the FVIII-specific immune memory seems to be characterized by the presence of circulating FVIII-specific memory B-cells belonging to the three isotype classes whereas FVIII-specific IgG-memory B-cells could not be found after a successful treatment. These results suggest an evolution of the pool of FVIII-specific circulating memory B-cells during the period of ITI. It would be interesting to study the FVIII-specific memory B-cells at the different periods of ITI (before, during and at the end of the protocol).The significance of FVIII specific memory B-cells in HA patients without inhibitor deserve to be study.

Disclosures
No relevant conflicts of interest to declare.
Hypoplastic Myelodysplastic Syndrome (h-MDS) Is a Distinctive Clinical Entity with Poorer Prognosis and Frequent Karyotypic and FISH Abnormalities Compared to Aplastic Anemia (AA).
Authors: Koh Youngil , Lee Hye Ryun , Song Eun Young , Kim Hyun Kyoung , Kim Inho , Yoon Sung-Soo , Lee Dong Soon , Park Seonyang , Park Myoung Hee , Kim Byoung Kook 
Published: October 2019

Abstract
Abstract 3199
Poster Board III-136
Differences between hypoplastic MDS (h-MDS) and aplastic anemia (AA) are not defined. Role of karyotype and fluorescent in situ hybridization (FISH) in these diseases is not established.
Medical record review at Seoul National University Hospital between 1990 and 2008 was performed. Patients diagnosed as either h-MDS or AA based on morphology was reviewed. We assessed overall survival (OS) and leukemic conversion.
369 AA and 40 h-MDS patients (median age 39 years, range 15-82) were analyzed. 235 and 165 patients underwent karyotyping and FISH at diagnosis respectively. Compared to AA, karyotypic abnormality, 5q deletion, trisomy 8 and trisomy 1q FISH abnormalities were more frequently found in h-MDS. Median OS of h-MDS was shorter than AA (60 vs. 219 months, p<0.001) with prognosis of h-MDS falling between severe and very severe AA. Patients with h-MDS had more frequent leukemic conversion (p<0.001) than AA patients. Karyotypic abnormality was not prognostic in AA (p=0.225). For h-MDS, complex karyotype and trisomy 1q FISH abnormality predicted poor prognosis.
The prognosis of h-MDS falls between severe and very severe AA. h-MDS accompanies frequent karyotypic and FISH abnormality and is prone to leukemic conversion. Complex karyotype and trisomy 1q FISH abnormality may have a prognostic role in h-MDS.
Table 1 Characteristics of patients according morphologic classification in 409 patients Characteristics Aplastic anemia (N=369) Hypoplastic MDS (N=40) p-value Age (median) 38.0 49.5 0.005 Gender 0.846 Male 197 22 Female 172 18 White blood cell (mean) (/μL) 2724 3042 0.368 Reticulocyte count (mean) (%) 1.1 1.8 0.007 Hemoglobin (mean) (g/dL) 8.3 7.9 0.357 Platelet (mean) (/μL) 44130 109000 0.008 Severity of cytopenia* 0.007 Moderate 244 36 Severe 96 4 Very severe 28 0 PNH component NA Present 15 NA Absent 351 NA IPSS risk category NA Intermediate-1 NA 25 Intermediate-2 NA 4 High NA 1 Oxymetholone administration# 0.005 Yes 167 9 No 196 30 Immunosuppressive treatment# 0.005 Yes 114 4 No 249 35 Stem cell transplantation# 1.000 Yes 49 5 No 314 34
Figure 1 OS of patients according to disease subtype h-MDS had inferior OS compared to AA in general (A), and its prognosis falls between SAA and VSAA (B). h-MDS had shorter OS compared to AA even stratified by the degree of cytopenia. IPSS score had a prognostic impact on h-MDS (D). Figure 1. OS of patients according to disease subtype h-MDS had inferior OS compared to AA in general (A), and its prognosis falls between SAA and VSAA (B). h-MDS had shorter OS compared to AA even stratified by the degree of cytopenia. IPSS score had a prognostic impact on h-MDS (D).

Disclosures
No relevant conflicts of interest to declare.
Mechanisms of Erythropoietic Failure in Shwachman Diamond Syndrome Caused by Loss of Ribosome-Related Protein SBDS.
Authors: Sen Saswati , Wang Hanming , Adams Sally-lin , Yau Janice , Zhou Kim , Dror Yigal 
Published: October 2019

Abstract
Abstract 3203
Poster Board III-140
Anemia occurs in 60% of patients with Shwachman Diamond Syndrome (SDS). Although bi-allelic mutations in SBDS cause SDS, it is unclear whether SBDS is critical for erythropoiesis and what the pathogenesis of anemia is in SDS. We hypothesize that SBDS protects early erythroid progenitors from apoptosis by promoting ribosome biosynthesis and translation. During early erythroid differentiation of human K562 cells and primary CD133+ cells, a prominent upregulation of SBDS by RT-qPCR was found. SBDS deficiency by vector-based shRNA led to impaired cell expansion of differentiating K562 cells due to accelerated apoptosis and a mild reduction in proliferation. Furthermore, the cells showed general reduction of 40S, 60S, 80S ribosomal subunits, loss of polysomes and impaired global translation during differentiation. Both cell expansion and translation defects were rescued upon re-introduction of SBDS in K562 cells. Interestingly, leucine partly corrected the cell expansion and translational defects of non-differentiating SBDS-deficient K562 cells, while differentiating SBDS-deficient K562 cells showed improved cell expansion in the presence of additional translation stimulators such as IGF-1. SBDS-knockdown CD133+ cells showed increased BFU-E colony formation under conditions with leucine and a combination of leucine and IGF-1 treatment. Although the erythroid cell expansion defect in K562 cells is independent of p53 as these cells do not express the gene, an upregulation of TAp73, was found in resting SBDS deficient K562 cells. However expression of TAp73 was lost during differentiation. DNp63 was also not upregulated in SBDS-deficient K562 erythroid cells. These results demonstrate that the role of SBDS in non-differentiated cells versus differentiated cells represents two dynamic scenarios and that SBDS plays a critical role in erythroid expansion by promoting survival of early erythroid progenitors and in maintaining ribosome biogenesis during erythroid maturation through a pathway independent of p53 family members.

Disclosures
No relevant conflicts of interest to declare.
Activity of Serono-AS703569, a Dual Inhibitor of Bcr-Abl and Aurora Kinases in Bcr-Abl Transformed Cells, Is Dependent On Aurora B Inhibition, and Is Not Affected by the Presence of the Highly Imatinib Resistant Bcr-Abl Mutation T315I.
Authors: Seitz Anna Katharina , von Bubnoff Nikolas , Sarno Samantha M. , Peschel Christian , Duyster Justus 
Published: October 2019

Abstract
Abstract 3247
Poster Board III-1
The tyrosine kinase inhibitor Imatinib is the gold standard in conventional treatment of CML. However, the emergence of resistance to IM remains a major problem. Alternative therapeutic strategies of IM-resistant BCR-ABL positive leukemias are urgently needed. One promising target for anticancer therapeutics is represented by the Aurora kinase family. These serine/threonine kinases are involved in regulating multiple steps of mitosis, including formation of bipolar spindle, chromosome alignment, spindle checkpoint function and cytokinesis.
We report on studies accomplished with a small molecule inhibitor AS703569 (Merck Serono), which targets Bcr-Abl and Aurora kinases A-C. We could show that AS703569 exhibited strong anti-proliferative and pro-apoptotic activity against murine BaF3- cells ectopically expressing wild type (wt) or IM-resistant BCR-ABL mutants, including those harbouring the strongly resistant T315I mutation. This effect was observed already at rather low-AS703569 concentrations, at which Aurora- but not the Bcr-Abl kinase was inhibited. Furthermore, in cell cycle analysis we observed cells with a large 4N peak and DNA content more than 4N, indicating extensive polyploidisation, a consequence of continued cell cycle progression in the absence of cell division. Recent studies have revealed that this phenotype is based on suppression of Aurora B kinase activity, indicating that Aurora B inhibition is the major effect of AS703569 in Bcr-Abl positive cells. To confirm this assumption we designed MSCV based retroviruses encoding different point mutations in the Aurora B ATP binding site, which should lead to resistance against AS703569. By this strategy we were able to identify an AS703569 resistant mutant (Aurora B G216V). This mutant shows significant resistance in vitro and is able to augment the antiproliferative capacity of AS703569 in Bcr-Abl positive cells. Taken together, our data demonstrate that anti-proliferative effects of AS703569 in Bcr-Abl positive cells are primarily mediated by functional inhibition of Aurora kinases, especially of Aurora kinase B. Since Aurora kinases are clearly implicated in tumorgenesis, they will become a high potential therapeutic target for anticancer therapy.

Disclosures:
No relevant conflicts of interest to declare.
Downregulation of THAP11 by Bcr-Abl Promotes c-Myc-Mediated CML Cell Proliferation.
Authors: Yokota Daisuke , Nakamura Satoki , Takemura Tomonari , Hirano Isao , Fujisawa Shinya , Takeshita Kaori , Ono Takaaki , Shigeno Kazuyuki , Ohnishi Kazunori 
Published: October 2019

Abstract
Abstract 3255
Poster Board III-1
[Background and Purpose] THAP11 (thanatos-associated protein 11) is one of the zinc-dependent, sequence-specific DNA-binding factors, which regulate cell proliferation, apoptosis and cell cycle. It has been reported that THAP11 is ubiquitously expressed in normal tissues and frequently downregulated in several tumors. In CML cells, we found that THAP11 expression was inhibited. We investigated the mechanisms of the suppression of THAP11 and its function in CML cell proliferation. [Methods] The cells used in this study were human CML cell lines, K562 and Meg01 cells. Primary CML cells were obtained from the bone marrow of CML (CP) patients. Human normal mononuclear cells (MNCs) were isolated from bone marrow of healthy volunteers after obtaining informed consents. For analysis of THAP11 mRNA expression, quantitative RT-PCR was performed in all cell lines treated with Abl kinase inhibitors (STI571, AMN107, and BMS354825). For proliferation analysis and the expression of c-Myc in CML cells, MTT assays, western blot and cell cycle analysis were performed in all cell lines transfected with Bcr-Abl siRNA, THAP11 siRNA, or THAP11 cDNA respectively. Moreover, THAP11 expression, c-Myc expression, and the colony counts of CFU-GEMM, CFU-GM, and BFU-E were analyzed in CML stem/progenitor cells transfected with Bcr-Abl siRNA or treated with Abl kinase inhibitors. [Results] In CML cell lines treated with Abl kinase inhibitors or transfected with Bcr-Abl siRNA, the expressions of THAP11 and c-Myc mRNA and protein were significantly increased compared to untreated cells. On the other hand, in CML cells transfected with the THAP11 cDNA, the c-Myc expression was suppressed. The overexpression of THAP11 induced G1 cell cycle arrest through p27 and p21 accumulation, and inhibited the CML cell proliferation. Moreover, in CML stem/progenitor cells obtained from patients with CML, the transfection with Bcr-Abl siRNA or treatment with Abl kinase inhibitors increased the expression of THAP11 mRNA and protein, and decreased the c-Myc expression and the counts of CFU-GEMM, CFU-GM and BFU-E. [Conclusion] Our results demonstrated that the Bcr-Abl suppressed the expression of THAP11, the depletion of THAP11 induced c-Myc expression, and induced the proliferation of CML cells through cell cycle progression. Moreover, induction of THAP11 expression inhibited the proliferation of CML stem/progenitor cells.

Disclosures:
No relevant conflicts of interest to declare.
FluBup-ATG-TBI for High-Risk or Advanced Adult ALL in Remission: A Retrospective Review of a Mature Cohort.
Authors: Daly Andrew , Stewart Douglas A. , Chaudhry Ahsan , Bahlis Nizar J , Brown Christopher , Duggan Peter , Geddes Michelle , Savoie Mary Lynn , Storek Jan , Yang Maggie , Russell James A. 
Published: October 2019

Abstract
Abstract 3384
Poster Board III-272

Purpose:
Hematopoietic stem cell transplantation (HSCT) is routinely offered to suitable candidates with high-risk or advanced acute lymphoblastic leukemia. In this report we describe our experience with a novel conditioning regimen, previously reported to confer low TRM and high OS in AML, in this population.

Patients and Methods:
Between 05/2000 and 06/2008 44 patients with high-risk (either adverse cytogenetics, age > 35 or high WBC at diagnosis) or advanced (>CR1) ALL received HSCT after myeloablative conditioning using Fludarabine 50 mg/m2 days -6 to -2, Busulfan 3.2 mg/kg days -5 to -2, and TBI 2 Gy x 2 doses. GVHD prophylaxis was with rabbit ATG 0.5 mg/kg day -2, then 2 mg/kg days -1 and 0, CyA (tapered on day +56) and short-course methotrexate. All patients were in remission at the time of transplant. Imatinib mesylate (Gleevec) was not used routinely before or after transplant for patients with BCR-Abl+ ALL. Median (range) follow-up of surviving patients is 4.3 (1.0 – 9.0) years. All patients were followed for at least 1 year after BCT.

Results:
The cohort consists of 32 patients with high-risk (median age 40 (19-64) years) and 12 patients with advanced (median age 25 (19-65) years) disease who received bone marrow (n=5), G-CSF mobilized blood stem cells (n=38) or umbilical cord blood stem cells (n=1) from 25 related (21 fully-matched) or 19 unrelated (16 fully-matched) donors. Median times to neutrophil and platelet engraftment were 14 (11-28) days and 18 (9-105) days, respectively. Five patients did not require platelet transfusion. Cumulative incidences of grade II-IV and grade III-IV acute GVHD were 53.2% (95% CI 36.3%-67.5%) and 20.6% (95% CI 3.5%-47.6%), respectively. Chronic GVHD complicated 55% (95% CI 38.4%-68.8%) of transplants. Six patients (13.6%) died in remission before day +100. Event-free and overall survivals at 5 years were 56.7% (95% CI 39.1%-71.0%) and 66.0% (95% CI 48.8%-78.6%), respectively. Nine patients (20%) died in remission, 6 (14%) died after relapse and two patients remain alive following second transplants for relapsed disease. Five of 11 patients age > 50, 8/12 patients with advanced disease and 13/23 patients with adverse-risk cytogenetics remain alive.

Conclusion:
We found encouraging results with FluBup-ATG-TBI in a cohort of patients with advanced or high-risk ALL. These results warrant comparison with other conditioning regimens in a randomized, multi-center study.

Disclosures:
Daly: Hoffmann-Laroche: Advisory Board, Honoraria. Stewart:Hoffmann La Roche: Advisory Board, Honoraria, Research Funding.
Induction Chemotherapy Followed Immediately by Busulfan-Based Reduced Conditioning and Allografting in Elderly Patients with Advanced MDS or sAML.
Authors: Kröger Nicolaus , Zabelina Tatjana , Wolschke Christine , Lellek Heinrich , Stübig Thomas , Lestin Maite , Alchalby Haefaa , Ayuk Francis , Bacher Ulrike , Fehse Boris , Zander Axel R. 
Published: October 2019

Abstract
Abstract 3387
Poster Board III-275

<>Introduction:
Allogeneic stem cell transplantation after a dose-reduced conditioning has become a reasonable treatment option for elderly patients with MDS/sAML. For patients with high number of blasts prior transplantation, the risk of relapse is considerably. To reduce the risk of relapse after dose-reduced allograft we performed a study using an anthracycline based induction chemotherapy (amsacrine, cytosine-arabinoside, fludarabine) followed immediately by a reduced intensity conditioning therapy consisting of busulfan (8mg/kg).

Patients and Methods:
Between November 2005 and November 2008, 49 patients with MDS (n = 24), CMML (n = 8) and sAML (n = 17) and a median age of 61 years (r: 26 – 73) and a median number of 13% blasts were included. Stem cell source were unrelated (n = 43) or related donor (n = 6).

Results:
No graft failure was observed and the median time to leukocyte engraftment (> 1.0 × 109 /l) was only 10 days (r: 7 – 32). The incidence of acute graft-versus-host disease grade II to IV was 39 % and of grade III / IV was 14 %. Chronic GvHD was noted in 57 % of the patients, which was limited in 35 % and extensive in 32 % of the patients. After a median follow-up of 15 months (r: 3 – 35) the two-years estimated disease-free and overall survival was 49 % (95 % CI 33 – 65 %) and 54 % (95 % CI 39 – 69 %), respectively. The 1 year cumulative incidence of treatment-related mortality was 29 % (95 % CI 15 – 43 %). The 2 year cumulative incidence of relapse was 18 % (95 % CI 6 – 30 %). Patients with fully matched related or unrelated donor had a better survival than patients transplanted from mismatched donor (69 % vs. 37 %; p=0.06).

Conclusions:
A sequential approach using anthracycline based induction chemotherapy followed immediately by a busulfan based reduced conditioning regimen and allogeneic stem cell transplantation from related and unrelated donors resulted in a fast engraftment and a relative low risk of relapse in elderly patients with advanced MDS or sAML. To lower the therapy related mortality a careful donor selection is mandatory.

Disclosures:
No relevant conflicts of interest to declare.
Interim Restaging FDG-PET/CT to Guide Use of High Dose Sequential Induction Therapy with Rituximab-Dose-Intensive Cyclophosphamide, Etoposide, Cisplatin (RDICEP) and Rituximab-Carmustine, Etoposide, Cytarabine, Melphalan (RBEAM) and Autologous Stem Cell Transplantation (ASCT) for Poor Prognosis Diffuse Large B-Cell Lymphoma (DLBCL). ClinicalTrials. Gov Identifier: NCT00530179.
Authors: Stewart Douglas A. , Duggan Peter , Bahlis Nizar J , Daly Andrew , Geddes Michelle , Kloiber Reinhard , Fibich Christian , Macdonald David Blair , Bence-Bruckler Isabelle 
Published: October 2019

Abstract
Abstract 3414
Poster Board III-302

Purpose
Approximately 50-55% of patients (pts) with stage 3-4 DLBCL and elevated serum LDH achieve long-term event-free survival (EFS) following R-CHOP chemotherapy. A prospective, multicentre, phase II clinical trial was designed to evaluate the use of high dose sequential therapy with RDICEP then RBEAM/ASCT for such pts who have positive interim restaging FDG-PET/CT scans after 2 cycles of RCHOP.

Patients and Methods
Pts were eligible if they were HIV-, 18-65 years of age, and had stage 3-4 DLBCL with elevated serum LDH. An FDG-PET/CT scan was performed 10-15 days following the second cycle of R-CHOP. Pts with negative interim restaging PET scans completed 4 further cycles of RCHOP, whereas pts with positive PET scans (more than 1 site with uptake more intense than background liver) received one cycle of RDICEP (Rituximab 375mg/m2 day 1 and 8, C 1.75g/m2 d2-4, E 350mg/m2 d2-4 P 35mg/m2 d2-4, G-CSF d15-21 and autologous blood stem cell collection by apheresis d21or 22) followed by one cycle of RBEAM/ASCT (Rituximab 375mg/m2 day -6 and +14, BCNU 300mg/m2 d-6, E 200mg/m2 d-5to-2, A 400mg/m2 d-5to-2, M 140mg/m2 d-1).

Results
Of the 36 pts who have been accrued from 5/2007-7/2009, 33 pts have undergone interim PET/CT restaging following 2 cycles RCHOP. All 33 pts had IPI scores 3-5, the median age was 55 years (range19-65) with 7 pts (21%) older than 60 years, 20 (61%) had ECOG status 2-4, 28 (85%) had stage 4, 22 (67%) >1 extranodal site. At a median follow-up of 12mo, the 1 year OS and EFS rates for all 33 pts are 82% (95%CI = 66-98%) and 76% (95%CI = 58-83%), respectively. Interim restaging PET/CT was positive for 16 pts and negative for 17 pts. The EFS rates for PET+ and PET- pts are 78% (95%CI = 57-100%) and 66% (95%CI = 36-99%), respectively (logrank p=0.97). To date, 4 pts have died, 3 from lymphoma at 6, 10, 11 months post-RCHOP1, and 1 from sepsis and necrotic bowel on day 5 post-ASCT.

Conclusions
Preliminary results of this phase II study are encouraging, and suggest that high dose induction therapy with RDICEP and RBEAM/ASCT might improve EFS for poor prognosis DLBCL with positive interim restaging PET/CT. Accrual will continue to target ≥ 35 PET+ and ≥35 PET- pts.

Disclosures
Stewart: Hoffmann La Roche: Advisory Board, Honoraria, Research Funding. Off Label Use: Rituximab with High Dose Chemotherapy and Autologous Stem Cell Transplantation for DLBCL. Bence-Bruckler:Hoffmann La Roche: Honoraria, Research Funding.