bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Mechanisms of Synergistically Cytotoxicity Induced by Homoharringtonine and Aclarubicin in Acute Myeloid Leukemia Cells
Authors: Wang Lei , Jin Jie 
Published: October 2019

Abstract
Abstract 4313
Previous studies showed HAA regime [HHT (homoharringtonine), cytarabine and ACR (aclarubicin)] resulted in a high complete remission (CR) rate and a better overall survival (OS) rate in patients with primary acute myeloid leukemia. To confirm if a synergistically cytotoxicity was found in AML cells, we investigated the antitumor effect relationship of HHT and ACR against AML cells. Using in vitro system, we demonstrated that simultaneous exposure to HHT and ACR resulted in strong synergistic anti-proliferative effect and apoptosis inducing in AML cells. In vivo, combination of HHT and ACR may be result in a favorable survival in AML xenograft mice. The assay of microarray gene expressing profiling highlighted apparent difference in expression of PI3K gene and WNT3a gene between cells treated by HHT and cells exposure to ACR. Furthermore, decreased expression of PI3K110 and P-AKT protein were observed in AML cells treated with HHT for 3h while no significant change in the expression of two proteins was observed in 90nM of ACR-treated cells. Western Blot analysis also showed ACR could obviously inhibit WNT3a and β-catenin protein levels in AML cells after 3 hours exposure. Although HHT could not inhibit WNT3a protein, it also could apparently down-regulate expression of β-catenin in AML cells. Simultaneous decrease of PI3K signal and WNT3a signal was induced by the combination of HHT and ACR in AML cell lines and primary AML cells. To explore possible targets of synergistically cytotoxity induced by combined HHT/ACR, we silenced wnt3a expression by RNA interference. Then we found suppression of wnt3a expression could enhance the cytotoxity of HHT and AKT inhibitor. Moreover, combining ACR with AKT inhibitor resulted in a synergistically cytotoxic effect too. β-catenin is a shared molecular in both AKT pathway and WNT pathway. Up-regulating of β-catenin expression failed to reduce cell apoptosis induced by HHT plus ACR while partially decrease the growth inhibition rate caused by combining treatment. β-catenin is required for the self-renewal of AML-LSC. Our study also suggests that combining HHT and ACR may synergistically induce apoptosis in LSC-enriched cells. These results indicate that simultaneously inhibiting activity of PI3K/AKT pathway and WNT/β-catenin pathway is a possible mechanism of synergistically cytotoxity induced combinated HHT/ACR in AML cells.

Disclosures:
No relevant conflicts of interest to declare.
The Efficacy of Time-Sequential Administration of GO After Conventional Chemotherapy for AML
Authors: Takada Satoru , Sato Naru , Kobayashi Nobuhiko , Takumi Hoshino , Hatsumi Nahoko , Sakura Toru 
Published: October 2019

Abstract
Abstract 4338

Background and aim:
Gemtuzumab ozogamicinamicyn (GO) is an anti-cancer drug for acute myelogenous leukemia (AML), which targets CD33 positive leukemic cells. It has been approved by basis of effectiveness for refractory and relapse AML as single agent. However, the optimal method of administration is also currently under investigation. We evaluated the efficacy of time-sequential administration of GO after conventional chemotherapy as consolidation therapy for AML.

Subjects and methods:
AML patients in second complete remission (CR), who received time-sequentially GO after conventional chemotherapy as consolidation, were included. The duration of second CR (+CRi), overall survival, and toxicity were examined retrospectively. To evaluate the efficacy, the duration of first CR and second CR (+CRi) was compared.

Result:
Ten patients received time-sequentially GO followed by conventional chemotherapy. Six patients were male, and four were female. Median age was 69 (62–79) years old. At the onset of AML, 7 patients had normal karyotype, 2 patients inv (16), and one patient trisomy 8, respectively. All patients were treated in lamina airflow room at the beginning of chemotherapy. All but one patient received GO 3mg/‡uat day 10 after short MEC therapy (MIT 7mg/‡u day1–3, VP16 80mg/‡u day1–5, AraC 100mg/‡u day1–5). One patient received 6 mg/‡uat day 7 after short MEC therapy. Hydrocortisone was administered before and after GO administration to prevent infusion reaction. Prevention for veno-occulusive disease was not performed. Six patients received 3 courses of treatment, one patient 2 courses, and 3 patients one course, respectively. The median duration of second CR (+CRi) and overall survival from second CR was 376 (56–2100) days and 576 (123–2099) days, respectively. In eight of ten patients, the duration of second CR was longer than first CR. All patients experienced Grade 4 toxicities of neutropenia and thrombopenia. Median period when neutrophils were less than 500/μl was 16 (9–35) days. Non-hematologic toxicities of grade 3 or more were sepsis for7 patients, febrile neutorpenia for2 patients, loss of appetite for one patient, liver dysfunction for one patients, and cardiac dysfunction for one patient. Veno-occulusive disease and infusion reaction was not experienced. Treatment-related death was not observed.

Conclusion:
Although our experience has been limited, time-sequential administration of GO after conventional chemotherapy as consolidation therapy in second CR was very effective. Non-hematological toxicities except infections were limited. As bone marrow suppression caused by this treatment is very strong, it is very necessary to pay enough attention to infectious disease.

Disclosures:
No relevant conflicts of interest to declare.
Standard Administration and Fractionated Administration of Gemtuzumab Ozogamicin for Patients with Relapsed and Refractory Acute Myeloid Leukemia
Authors: Yahagi Yuichi , Usui Noriko , Yamaguchi Yuko , Dobashi Nobuaki , Yano Shingo , Takei Yutaka , Sugiyama Katsuki , Takahara Shinobu , Ogasawara Yoji , Saito Takeshi , Kasama Kinuyo , Yokoyama Hiroki , Kamiyama Yutaro , Katsube Atsushi , Aiba Keisuke 
Published: October 2019

Abstract
Abstract 4342
(Purpose) We retrospectively analyzed the data regarding patients who received fractionated administration (FR) of gemtuzumab ozogamicin (GO) and standard administration (ST) of GO for the treatment of their refractory and relapsed acute myeloid leukemia in order to review the efficacy and safety of GO in each type of administration. (Method) The patients with relapsed and refractory acute myeloid leukemia (excluding patients with acute promyelocytic leukemia) who were treated with the ST of GO received 2 doses of monotherapy with 9 mg/m2 GO as a 2-hour intravenous (iv) infusion with a 14–28-day interval. The fractionated GO group received 2 doses of GO monotherapy administered as a 2-hour iv infusion of 3 mg/(m2·day) on days 1, 3, and 5 with a 14–28-day interval. (Result) Eleven patients received ST and 9 received FR. The median age of all patients was 66.1 (55–77) years. Overall response rates (CR+CRp) in the ST and FR groups were 27% and 33%, respectively. The adverse events (grade 3–4) in the ST and FR groups were neutropenia (100% vs. 100%), thrombocytopenia (90.9% vs. 88.9%), and hypertransaminasis (18.2% vs. 0%). Grade 3–4 hypertransaminasis was seen only in the ST group. Infusion reactions occurred in 5 patients: 3 in the ST group and 2 in the FR group. The median CD33 positivity of blast cells of patients who received CR or CRp was 90.9% (78.2–99.5%). (Discussion) The response rates of the ST and FR groups were similar. However, the incidence of grade 3–4 hypertransaminasis tended to be higher in the ST group. These data suggest that FR of GO is less toxic than ST. Thus, FR of GO is safer than ST even for Japanese patients with acute myeloid leukemia.

Disclosures:
No relevant conflicts of interest to declare.
Role of CD74 in Mesenchymal Stem Cell Dysfunction in Patients with Acute Myeloid Leukemia
Authors: Patel Shyam Ajay , Rameshwar Pranela 
Published: October 2019

Abstract
Abstract 4344
Mesenchymal stem cell (MSC) dysfunction has been implicated in the biology of the acute myeloid leukemia (AML). Preliminary studies from our laboratory have demonstrated that MSCs derived from AML patients have diminished T cell immunosuppressive capacity, and these MSCs demonstrate signs of transformation. In the current study, we seek to explore the mechanisms of MSC dysfunction in patients with AML. Recent reports have implicated migration inhibitory factor (MIF) and its receptor CD74 in cancer progression. CD74 is a cell surface glycoprotein that also serves as the invariant chain for the class II major histocompatibility complex (MHC-II). The significance of these studies is two-fold: (1) CD74 participates in intracellular signal transduction via NF-kappaB, ERK, and PI(3)K pathways, thereby promoting cell proliferation, and (2) MHC-II invariant chain expression in MSCs may prevent tumor antigen loading and presentation to T cells, allowing for immune subversion. Our results show increased expression of CD74 on MSCs derived from AML patients. The readily targetable phenotype and the availability of anti-CD74 antibody milatuzumab merits further investigation into the role of CD74 in AML biology.

Disclosures:
No relevant conflicts of interest to declare.
A Software for the Prescription of Prophylactic Treatment of Venous Thromboembolism (VTE) in Hospitalized Patients. Evaluation of the Prescriptive Mode
Authors: Santi Roberto , Contino Laura , Davio Piero , Levis Alessandro 
Published: October 2019

Abstract
Abstract 4371

Background/Aim:
Using of a software for venous thromboprophylaxis prescription in hospitalized patients. Evaluation of the prescriptive mode in relation to the risk profile of the patient.

Materials and Methods:
Has been developed a software, which guides the physician to the choice of prophylaxis of VTE on the basis of a thromboembolic risk score (The Padua Prediction Score), renal function and the type of admission. We analyzed data derived from prescriptions over a period of 14 consecutive months.

Results:
3125 patients were included. 68% of the patients were “high-risk (HR)” and 32% at “low risk (LR)”. Were treated with drug therapy, 89% of HR patients and 40% of LR. 11% of HR patients were not treated for severe renal failure or high risk of bleeding.

Conclusion:
All HR patients were considered for thromboprophilaxis. 89 % of HR patients and 40% of LR were treated. In our initial experience the software is an effective tool to identify patients at high risk and more effective prophylactic strategy. Furthermore, the evaluation of creatinine clearance allows to assess the bleeding risk associated with prophylactic treatment.

Disclosures:
No relevant conflicts of interest to declare.
Minor Blood Group Antigen Disparities in Sickle Cell Disease Population
Authors: Kumar Mukesh , Shelia Palmer , Winkler Annie Marie , Eckman James R. 
Published: October 2019

Abstract
Abstract 4381

Introduction:
Red blood cell (RBCs) transfusion is the mainstay of treatment for sickle cell disease (SCD) patients and indications continue to expand. Differences in geographic origin between blood donors and sickle recipients has been posited as a cause of the high rate of alloantibodies in patients with sickle cell disease (Vichinsky et al. NEJM 1990; 322: 1617–21). Alloimmunization is one of the major limiting factors of obtaining compatible blood for transfusion and exchange transfusion compromising the management of patients with SCD. Mismatch in minor antigen distribution has been attributed as one of the main reasons for significantly high rate of alloantibodies in SCD patients. Here we describe the minor blood group antigen lacking in SCD patients and comparing with frequencies in white and black populations.

Methods:
Patients with diagnoses of SCD, confirmed by standard hemoglobin electrophoresis, who had at least one type and cross match done from 1995 through 2011 were included in this study. All patients are evaluated for K, C, E, S, Fya, Fyb, Jka and Jkb antigens in addition to ABO and RhD system before transfusion. Results were routinely recorded in the electronic database of the Georgia Comprehensive Sickle Cell Program at Grady Health System to improve patient transfusion management. The frequency of antigens was compared to published prevalence of antigens in Whites and African American population.

Results:
A total of 594 patients were identified with SCD who have been tested for antigens during this period, of these, 310 (52%) females and 284 (48%) males. Average age of the patients is 27 (range 3–84). Most common antigen lacking in SCD patients is from Kell blood group K (98%). About 9% of white population is positive for K. Frequency of E+ is 30% in white population and 2% in blacks while 83% of SCD patients lack E antigen. Overall antigen distribution and comparison included in Table 1.

Conclusion:
Mismatch of antigen expression in white population (mainly donors) especially for K, E, C and Fya; may explain why these are common antibodies detected in SCD patients Anti E (42.3%), Anti C (30.2%), Anti K (28.1%) and Anti Fya (18.3%) (Rosse et al, Blood, Vol 76, No 7). Given these antigen frequency differences, efforts should be made to increase blood donation in the African American population and at least limited phenotypic matching continues to be justified.

Disclosures:
No relevant conflicts of interest to declare.
Therapeutic Red Blood Cell Exchange in Sickle Cell Anaemia Using the Spectra Optia® Apheresis System
Authors: Sipurzynski-Budraâ Sabine , Sovinz Petra , Lanzer Gerhard , Schallmoser Katharina 
Published: October 2019

Abstract
Abstract 4383

Background:
Sickle cell disease, an autosomal recessive genetic blood disorder, is caused by abnormal hemoglobin (Hb) due to a substitution of valine by glutamic acid at β6 (HbS). Typical adverse events are vaso-occlusive crises due to obstruction of capillaries causing ischemia, pain and organ damage, as well as enhanced hemolysis and frequent hemolytic crises. Further complications may include acute chest syndrome and stroke. To prevent long-term sequelae, repeated blood transfusions are necessary to decrease erythropoiesis of sickle cells. We suggest that it may be more effective to reduce sickle cells by a red blood cell (RBC) exchange, which is advantageous in avoiding iron overload by transfusions.

Patient and Methods:
We report on a 10 year old boy suffering from the homozygote form of sickle cell anemia. RBC exchange was performed using the Spectra Optia® Apheresis System (Caridian BCT vers.5) when the patient's hematocrit (hct) was less than 26%. Traditional RBC exchange was modified by a depletion phase to improve efficacy. During this phase (= isovolemic hemodilution) HbS-containing red cells were removed without admixture of donor red cells by using plasma as replacement fluid. To prevent adverse side effects caused by adenine, the additive solution in the RBC concentrates was replaced by saline solution or plasma.

Results:
The therapeutic apheresis was feasible repeatedly via peripheral venous access (flow: 30 ± 3 mL/min, anticoagulant (AC) infusion rate 0.8 – 1.1mL/min/L total blood volume, inlet: AC ratio 13: 1) and no adverse side effects were observed. The median interval between the procedures was 42 ± 2 days. The depletion time (replacement fluid: plasma) was 25 ± 5 min, the exchange time 90 ± 10 min. The hct value at the end of the procedure was between 33 and 34%, the fraction of the patient's remaining cells (FCR) was 24 ± 2% (calculated by the device).

Conclusion:
RBC exchange with the Optia Spectra® System is a fast and safe method for reducing sickle cells, particularly efficient in combination with a depletion phase. Compared to blood transfusions alone, the HbS concentration declines rapidly by depleting and replacing sickle cells with normal RBCs without hyperviscosity or iron overload. However, only long-term surveillance and treatment of a larger patient collective will show whether it is possible to prevent vaso-occlusive crises and organ damage over a longer time period.

Disclosures:
No relevant conflicts of interest to declare.
Diminished Oxidative Stress Responses in Bone Marrow Stromal Cell Lines Derived From Fanconi Anemia (Fanc-D2−/−) Mice
Authors: Berhane Hebist , Epperly Michael W. , Cao Shaonan , Zhang Xichen , Shields Donna , Goff Julie , Sprachman Melissa , Wipf Peter , Li Song , Gao Xiang , Greenberger Joel S. 
Published: October 2019

Abstract
Abstract 4398
Fanconi Anemia (FA) is an inherited cancer susceptibility syndrome associated with a defect in one or more of the 15 FA pathway gene products leading to bone marrow failure, increased cellular sensitivity to DNA cross-linking agents and increased risk of myeloid leukemia. Underlying DNA repair vulnerabilities render FancD2−/−, a homozygous deletion recombinant negative mice, sensitive to whole body irradiation. We quantitated hematopoiesis in long term bone marrow cultures, and the radiosensitivity and oxidative responses of derived marrow stromal and IL-3 dependent hematopoietic progenitor cell lines derived from FancD2−/− mice on a C57BL/6 background (generously provided by Drs. A. D'Andrea and K. Parmar, Dana-Farber cancer Inst., Boston, MA). Long-term bone marrow culture stromal cell lines derived from FancD2−/− were compared to FancD2+/− or FancD2+/+. FancD2−/− long term marrow cultures showed decreased cobblestone islands, representative of hematopoietic stem cell generating foci, and production of non-adherent cells compared to wild type FancD2+/+ or heterozygous FancD2 +/− cultures (p = 0.0148) and produced fewer colony forming cells on day 7 and 14 compared to FancD2 +/− or FancD2 +/+ cell lines (p < 0.0001). FancD2−/− stromal cell lines showed decreased DNA repair by comet assay after irradiation to 5Gy (P<0.0001). Following irradiation to 5 or 10 Gy, FancD2−/− cells had an increased cell doubling time (44.1 + 0.7 and 54.2 + 7.8) compared to FancD2 +/+ cells (35.5 + 1.5hrs and 33.6 + 1.3,hrs p = 0.006 and 0.051, respectively). FancD2−/− cells had decreased baseline antioxidant levels compared to the FancD2 +/+ cells (0.55 + 0.11 and 0.91 + 0.17 trolox units, respectively). FancD2−/− cells at 24 hr following 10 Gy irradiation had 0.39 + 0.03 trolox units compared to 0.76 + 0.07 trolox units in FancD2 +/+ cells (p = 0.006). In clonogenic irradiation survival curve assays, FancD2−/− marrow stromal cells were radiosensitive (Do = 1.43 + 0.06 Gy, n = 4.98 + 0.65) compared to FancD2 +/+ (Do 1.70 + 0.09 Gy and n = 8.33 + 0.72, p = 0.0395 and 0.0040, respectively) or FancD2 +/− cells (Do = 1.67 + 0.08 and n = 3.63 + 0.44, p = 0.0348 and 0.1365, respectively). Furthermore, FancD2 +/− cells were more radiosensitive compared to FancD2 +/+ cells ((n = 3.63 + 0.44 or 8.33 + 0.72), p = 0.0003). Thus, the FancD2 gene controls several parameters of sensitivity to oxidative stress and ionizing radiation as demonstrated in mouse long-term marrow cultures and derived cell lines.

Disclosures:
No relevant conflicts of interest to declare.
FDG PET/CT May Overestimate Red Bone Marrow Volume
Authors: Spigelman Zachary Simon 
Published: October 2019

Abstract
Abstract 4405
Sambuceti, et al. (Eur. J. Nuclear Med Mol Imaging, Aug, 2012. 39: 1326–1338) used a computational FDG PET/CT model to estimate the volume of the bone marrow space and specifically “Red” or actively hematopoetic marrow in 102 nonmetastatic melanoma patients. 34.9 percent of all marrow space was estimated to be populated by “Red” Marrow. There was no associated pathologic bone marrow or peripheral blood count correlation of this FDG PET/CT model. In an attempt to define pathologic correlation of the findings of Sambuceti et al., 102 consecutive pathologic samples of femoral hip replacements were evaluated for their “Red” Marrow content and correlated with the patient's peripheral blood counts. The patients reviewed did not have active carcinoma or recent exposure to chemotherapeutic agents. 48/104(47.1%) of the samples obtained contained active “Red” Marrow”upon microscopic evaluation of femoral head and shaft samples stained with Hematoxylin and Eosin. Of these samples “Red' Marrow averaged 5.05 percent of the pathologic sample volume (range 0–40%) as opposed to 20–30 percent of the estimated bone marrow segmental space calculated to be populated by “Red” Marrow heads of long bones as defined by the FDG PET/CT model. In this study patient gender, height, BMI, weight, red marrow cellularity, peripheral white blood cell counts, platelets, hemoglobin, hematocrit, creatinine did not predict the extent of “Red” Marrow volume. Many variables may affect the results of these studies including: spotty metabolic activity of the marrow, clinical inflammatory effects of bone marrow in long bone heads, pathologic sampling errors, low study power, sample preparation and patient selection. Although there was no clear explanation for this overestimation of pathologic-FDG PET signal, the age of the populations were significantly different (55.9 years old in Sambuceti et al and 62.4 years old in this study). Age was found to have a significant correlation with “Red “Marrow volume in the Sambuceti et al study. The FDG PET scan evaluation may overestimate metabolic activity of “Red” Marrow and thus run the risk of obscuring other bone pathology. Therefore, prospective PET/CT-pathologic-clinical correlation studies are warranted in light of the prognostic, therapeutic, and diagnostic importance of “Red“Marrow activity in FDG PET/CT clinical staging of oncologic disease.

Disclosures:
No relevant conflicts of interest to declare.
Overexpression of the EphB4 Receptor Contributes to Imatinib Resistance in Chronic Myeloid Leukemia Through Regulating Mlcp and VAV1
Authors: Xiaoli Liu , Zhang Jinfang , Du Qingfeng , Xu Na , Xu Lulu , Xiao Xiaozhen , Zhou Xuan 
Published: October 2019

Abstract
Abstract 4421

Objective:
To study the role of EphB4 in imatinib (IM) resistant chronic myeloid leukemia (CML) and investigate the mechanism.

Methods:
We derived IM-resistant cells, K562-R cells, from wild K562 cells under gradually increasing IM concentrations. We analysed expression level of EphB4 in CML patients, wild K562 and K562-R cell lines by real-time reverse transcription PCR and Western blot analysis. Then we established stable under-expressing EphB4 cell (K562-R-EphB4-sh) lines. We analysed the sensitive for IM of K562, K562-R, K562-R-EphB4-sh cell lines by CCK8 assay. Microarray analysis was used to screen differential expression genes between K562-R and K562-R-EphB4-sh cell lines.

Results:
The mRNA and protein of EphB4 were significantly increased in IM resistant CML patients compared to IM sensitive CML patients (p<0.05). The Similar results were observed in K562-R and K562 cells (p<0.01). To analyze the role of EphB4 in IM resistance, EphB4 was knocked down with shRNA expressed by pLL3.7 lentivirus vector. We established stable under-expressing EphB4 cell line K562-R-EphB4-sh. RT-PCR and western blot analysis showed that mRNA and protein expression of EphB4 in K562-R-EphB4-sh cells were reduced (p<0.05). CCK8 assay found K562 cells (IC50 0.1207±0.0234μM), K562-R-EphB4-sh cells (IC50 0.7228±0.04752μM) were sensitive to IM but K562-R (IC50 2.8101±0.04674μM) still showed IM resistance (p<0.05). Those suggested K562-R-EphB4-sh cells resensitize to IM when the expression of EphB4 was down regulated. However, these cells were still less sensitive than K562 cells. Microarray analysis between K562-R and K562-R-EphB4-sh cell lines found 641 differential expression genes, most of them were related to cell adhesion and cell cytoskeleton. We confirmed MLCP and VAV1 were down regulated in K562-R-EphB4-sh cells compared to K562-R cell lines by western blot analysis.

Conclusion:
Our study suggest EphB4 receptor contributes to IM-resistant in CML through regulating cell adhesion molecular MLCP and VAV1, which may provide new biomarkers and contribute to] developping new drugs for the disease.

Disclosures:
No relevant conflicts of interest to declare.