bluuebunny/crossref_metadata_2025_split huggingface dataset:
hOCT1 Gene Expression Might Predict Molecular Response In Patients with Chronic Myeloid Leukemia
Authors: Zamora Lurdes , Cabezon Marta , Boqué Concha , Marce Silvia , Ribera Jordi , Dominguez Diana , Granada Isabel , Grau Javier , Xicoy Blanca , Fernandez Cristalina , de Sevilla Alberto Fernandez , Gallardo David , Ribera Josep-Maria , Millá Fuensanta , Feliu Evarist 
Published: October 2019

Abstract
Abstract 4838

Introduction:
Chronic myeloid leukemia (CML) is a clonal hematopoietic malignancy characterized by the presence of BCR/ABL fusion gene. The resulting protein has a high tyrosine kinase (TK) activity. The first-line treatment for CML is Imatinib, which allow the achievement of cytogenetic and molecular response in most of patients with CML in chronic phase. However, some patients do not respond to this treatment or lose their initial response. Imatinib has been reported to be incorporated into the cell through hOCT1 transporter (human organic cation transporter).
The aim of this study was to determine whether the expression of hOCT1 at diagnosis of CML influenced the achievement of molecular response.

Patients and Methods:
We analyzed hOCT1 gene expression by quantitative PCR in 42 patients at diagnosis and 18 months after treatment with Imatinib. We compared the expression with the presence of compleat molecular response (CMR) at 18 months. We consider CMR when the Ratio (BCR-ABL/ABL)×100 was <0.1% (after International Scale correction). For statistical analysis methods we have used Kolmogorov-Smirnov and Mann-Whitney nonparametric methods.

Results:
Of the 42 patients, 2 were in hematological response, 22 were in cytogenetic response and 18 in CMR at 18 months. We found a higher hOCT1 gene expression at 18 month than at diagnosis (53.3 versus 29.6, p<0.001) in all patients (Figure 1). We have found some tendency of higher hOCT1 expression at diagnosis in patients with CMR at 18 months than in those who did not had (25.5 versus 18.8, p = 0.07) (Figure 2).

Conclusions:
Partially funded by FICJ-P-EF-09, RD06/0020/1056 de RTICC and Novartis.
We want to thank Dr. David Marin for providing us plasmid for quantitative analysis.

Disclosures:
No relevant conflicts of interest to declare.
Fas and Fas Ligand Expression In Children with Acute Lymphoblastic Leukemia, Benign Hematological Diseases and Solid Tumors
Authors: Stiakaki Eftichia , Martimianaki Georgia , Kaparou Maria , Perdikogianni Chryssoula , Kalmanti Maria 
Published: October 2019

Abstract
Abstract 4853
Fas/FasL is a key pathway of cellular apoptosis. Fas receptor is expressed on membranes of both normal and neoplastic cells while, Fas ligand (FasL) mainly on activated T-lymphocytes. Fas-FasL abnormalities have been detected in malignancies and autoimmune diseases and implicated in resistance to treatment. The aim of the study was the determination of the levels of Fas, FasL and their coexpression in bone marrow cells of children with acute lymphoblastic leukaemia (ALL) at diagnosis, during the course of treatment and the comparison with relevant levels in other hematological and neoplastic diseases. Expression levels of Fas and FasL were determined with flow cytometry in children with ALL at diagnosis (ALLd, n=13), on day 15 of treatment (d15, n=6), on day33 (ALLd33, n=6), during consolidation (ALLhr, n=12) and at the end of therapy (ALLet, n=7) as well as in children with Langerhans Histiocytosis (LCH, n=4), cytopenias (Cytp, n=8) and solid tumors without bone marrow infiltration at diagnosis (STd, n=5) and on therapy (STther, n=6).

Results:
The lowest levels of Fas expression were detected at diagnosis of ALL and were gradually statistical significantly increased until remission of day 33 (ALLd vs ALLd33: 8.02±1.94 vs 24.04±6.11, p=0.035). At consolidation Fas levels were found to be decreased compared to day33 (16.1±4.18) and were again increased at the end of therapy (ALLd vs ALLet: 8.02±1.94 vs 24.96±7.95, p=0.024). On the contrary, FasL levels were gradually decreased and finally increased to similar to diagnosis levels at the end of treatment (ALLd: 4.59±1.41, ALLet: 5.89±1.99). In solid tumors at diagnosis Fas levels were similar to the ones while on chemotherapy (STd vs STth:16.04±2.2 vs 15.19±6.4). The highest FasL levels were detected in the group of STd with the relevant levels on treatment being lower in comparison (STd vs STther: 10.91±3.32 vs 2.92±0.79, p=0.052). In LCH both Fas and FasL levels were found to be as low as at ALL diagnosis. In cytopenias no significant difference was observed between groups for either Fas (11.05±4.49) or FasL (3.01±0.62). As for Fas+FasL+ coexpression no difference was evident between ALLd, ALLet and STd or STther [ALLd (0.73±0.38), ALLet (0.64±0.17), STd (0.68±0.095), STther (0.66±0.38)]. The lowest coexpreesion levels were observed in the group of cytopenias with statistical significant difference compared to STd (0.68±0.095 vs 0.26±0.08, p=0.031). In conclusion, at diagnosis of ALL Fas levels were expressed in lowest levels that were found to be gradually increased at remission and at the end of treatment. This finding probably correlates with the apoptotic process of the leukemia clone and possibly with response to treatment.

Disclosures:
No relevant conflicts of interest to declare.
Biphasic Roles for the Soluble Guanylyl Cyclase (sGC) In Platelet Activation In Mice
Authors: Zhang Guoying , Xiang Binggang , Skoda Radek C. , Smyth Susan S. , Du Xiaoping , Li Zhenyu 
Published: October 2019

Abstract
Abstract 486
The role of intracellular secondary messenger cGMP in platelet activation has been controversial, with both stimulatory and inhibitory roles reported. The platelet cGMP is believed to be predominantly synthesized by soluble guanylyl cyclase (sGC), which is activated by nitric oxide (NO). To specifically determine the role of sGC-dependent cGMP synthesis in platelet function and in vivo thrombosis and hemostasis, we produced mice harboring a “floxed” sGC beta1 allele. In the “floxed” sGC beta1 mice (sGC beta1fl/fl), the exons 7 and 8 of sGC beta1 gene and an inserted Neo cassette were flanked with three LoxP sites. Platelet-specific deletion of sGC beta1fl/fl allele was accomplished through breeding of the sGC beta1fl/fl mice with pf4-Cre recombinase transgenic mice. Immunoblotting showed the complete absence of this protein in sGC beta1fl/fl/Cre platelets. Mice lacking sGC beta1 in platelets appeared to develop normally and had normal blood counts, including platelets. Blood pressure of platelet-specific sGC deficient mice was comparable to that of wild-type littermates. Inactivating the sGC beta1 gene in platelets abolished cGMP production induced by either NO donors or platelet agonists that are known to activate endogenous NO synthesis, confirming that both the platelet agonist-induced and NO donor-induced platelet cGMP production are predominantly mediated by sGC. Platelets lacking sGC exhibit a marked defect in aggregation and secretion in response to low doses of platelet agonists, collagen and thrombin. Importantly, tail-bleeding times were significantly prolonged in the platelet-specific sGC deficient mice compared with the wild-type littermates. In a FeCl3-induced carotid artery thrombosis model, time to occlusive thrombosis was prolonged in the platelet-specific sGC deficient mice, compared to wild type littermates. Thus, the agonist-stimulated sGC activation is important in promoting platelet granule secretion and aggregation. On the other hand, NO donor SNP-induced inhibition of platelet activation was abolished in sGC-deficient platelets. However, at high concentrations (>100μM), SNP inhibited platelet activation in both wild type and sGC deficient mice, indicating that both cGMP-dependent and -independent mechanisms are involved in NO donor-induced inhibition of platelet activation. Together, our data demonstrate that sGC contributes to both agonist-induced platelet activation and NO donor-induced platelet inhibition.

Disclosures:
No relevant conflicts of interest to declare.
Immunodulatory Capacity of Mesenquimal STROMAL CELLS IS CONTROLLED by NON-Canonical NF-Kb PATHWAY
Authors: Haddad Rodrigo , Saldanha-araujo Felipe , Araujo Amélia , Covas Dimas T , Zago Marco A. , Panepucci Rodrigo Alexandre 
Published: October 2019

Abstract
Abstract 4865

Introduction:
Mesenquimal Stromal Cells (MSCs) possess immunosuppressive properties, becoming these cells a promising subject of study for future approaches in cell-based therapy. During co-culture with activated lymphocytes and probably through T-cell derived cytokines, MSCs are activated in order to become suppressive. Once MSCs are triggered, they acquire an inhibitory profile increasing the release of immunoregulatory factors, such as IDO, IFNγ, PGE2, NO and TGF-β, responsible for T-cell inhibition. In addition, expression of adhesion molecules, such as ICAM-1, and generation of regulatory T cells subsets, such as CD69+ T cells, are important in immunosuppressive property of human MSCs. However, the exact mechanisms underlying the immunomodulatory functions of MSCs remain largely unknown. NF-kB comprises a family of inducible transcription factors that serve as important regulators of the host immune and inflammatory responses. The NF-kB signals are activated via canonical (mediated mainly by RelA-p50) and/or non-canonical (mediated by RelB-p52) pathways in response to diverse stimuli. Given the immunomodulatory properties of MSCs and the possible involvement of NF-Bk pathway in this effect, here, it was explored the role of non-canonical NF-KB signaling in the immunomodulatory capacity of MSCs cocultured with activated T cells.

Methods:
siRNAs targeting RelB were transfected into MSC with lipofectamine. siRNAs C- were used as negative control and siRNA-FITC as transfection control. After 24 hours, immunomagnetically purified CD3+ T cells were stained with CFSE, activated by anti-CD2/CD3/CD28 beads and cultured in the presence of MSCs. After 3 days, flow cytometry was performed to observe the transfection efficiency, T cell proliferation and percentage of CD69+ T regulatory cells. Additionally, RNA from MSCs was extracted and RelB and ICAM-1 mRNA expression were quantified by Real-time PCR.

Results:
The transfection efficiency was around 75% and RelB mRNA level was reduced by 80% in MSCs transfected with siRNA RelB compared to siRNAs C- transfected cells. Compared to MSCs previously transfected with siRNA C- and co-cultured with activated T cells, MSCs transfected with siRNA RelB resulted increasing of 22% in T cell proliferation and decreasing of 9,2% and 30% in the CD69+ regulatory T cells generation and ICAM-1 expression respectively.

Conclusion:
Non-canonical NF-kB pathway, mediated by RelB, may be partially involved in acquisition of the inhibitory profile by decreasing T cells proliferation, and increasing the expression of ICAM-1 and the generation of CD69+ regulatory T cells.

Disclosures:
No relevant conflicts of interest to declare.
Comparison Between CD20-Negative and CD20-Positive Diffuse Large B Cell Lymphoma; Characteristics and Clinical Outcome
Authors: Jo Jungmin , Yoo Changhoon , Ahn Yongchel , Park Seong Joon , Kim Shin , Lee Dae Ho , Kim Sang We , Lee Jungsin , Suh Cheolwon 
Published: October 2019

Abstract
Abstract 4891

Background
CD20 is a non-glycosylated phosphoprotein expressed on the surface of all mature B-cells. CD20 is expressed on all stages of B cell development except the first and last. However, complete lack of CD20 expression occurred in a few cases without previous rituximab (R-) treatment. The immunohistochemostry (IHC) studies which we used were not perfect for confirmation of expression. However, we intended to investigate characteristics and clinical outcome of CD20-negative diffuse large B-cell lymphoma (DLBCL), not detected with usual method, and to compare with CD20-positive.

Methods
The records of Non-Hodgkin's Lymphoma patient registry were reviewed in Asan Medical Center. Between September 2003 and February 2009, a total of 407 patients were diagnosed DLBCL and 16 patients (3.9%) out of 407 confirmed CD20-negative DLBCL by IHC. The rest of patients (n=391) were CD20-positive and unconfirmed cases were excluded. Retrospective analysis of complete response (CR), disease-free survival (DFS), and overall survival (OS) was performed.

Results
The median age was 60.5 years old (range 31–81) in CD20-negative patients. Ten patients were males. The Ann Arbor stage was I in 3 patients, II in 3 patients, and III or IV in 10. Six patients were low risk group, 7 patients in intermediate, and 3 in high risk group according to international prognostic index (IPI). Most of patients (62.5%) received cyclophosphamide, doxorubicin, vincristin, and prednisone (CHOP) chemotherapy in CD20-negative and 295 patients (75.4%) with R-CHOP in CD20-positive DLBCL. The Baseline characteristics was not different in both groups except Hans classifier (p=0.02).
With a median follow-up time of 32.3 months (range 0.5–83.4), the CR rate was 73.5%, the 3-year OS was 69.5%, and 3-year DFS 74.2% in all patients. CD20-positive and CD20 negative groups had a CR rate of 73.7%, 68.8% (p=0.146), respectively, a 3-year OS of 70.7%, 40.0% (p=0.003), a 3-year DFS of 75.4%, 44.6% (p< 0.001), respectively. The 3-year OS and DFS also had significant difference with adjusted IPI (p<0.001, respectively).

Conclusions
CD20-negaive DLBLC was not infrequently with usual IHC method (around 4%). The survival outcome was poor compared with CD20-positive DLBLC because of high relapse rate. It was caused without rituximab treatment in CD20-negative. Development of novel target agents like rituximab should be explored to improve outcome and maintain the CR status of CD20-negative DLBCL.

Disclosures:
No relevant conflicts of interest to declare.
A Refractory Stage IVb Thymoma Responded Completely to a Combination of Dasatinib and Prednisone but Poorly to Either One Alone
Authors: Lian Eric C. Y. , Matsangou Maria , Liu Diana 
Published: October 2019

Abstract
Abstract 4925

Introduction:
Thymomas are rare tumors for which there is little randomized evidence to guide treatment and therefore, therapeutic options to cure advanced malignant thymomas are limited. We hereby report the first clinical outcome of combined dasatinib and prednisone therapy in a patient with heavily treated stage IVB malignant thymoma.

Case Presentation:
A 41 year old white male presented with fatigue, fever and granulocytopenia. He soon developed myasthenia gravis and aplastic anemia. Computer tomography showed a mediastinal mass, pleural thickening, splenomegaly and mesenteric nodes; biopsy of mediastinal mass revealed a malignant thymoma. Prednisone for 6 weeks along with antithymocyte globulin and cyclosporine were started for myasthenia gravis and aplastic anemia. Chemotherapy for unresectable thymoma was soon initiated with ADOC (Cisplatin, Doxorubicin, Vincristine, and Cyclophosphamide), but only small partial response was noted. After failing to show response to another three lines of therapy, we commenced therapy with dasatinib 75 mg twice daily. Thymoma showed partial response to dasatinib initially but soon became resistant and progressed. When prednisone 100 mg daily was added, a complete response was observed.

Conclusion:
A patient with stage IVB thymic carcinoma failed to respond well 3 lines of combination chemotherapy, and neither to prednisone or dasatinib alone. When dasatinib is combined with prednisone, it induced a complete response.

Disclosures:
Off Label Use: Dasatinib is an oral dual BCR/ABL and Src family tyrosine kinase inhibitor. It is a potent inhibitor of Imatinib resistant KIT activation loop mutants and induces apoptosis in mast cells and leukemic cells. At higher concentrations, Dasatinib also inhibits c-Kit, PDGFR and EphedrinA2. it has currently FDA approval for treatment of adults in all phases of chronic myeloid leukemias with resistance or intolerance to prior therapy, including Gleevec. The second indication for Dasatinib, is for the treatment of Ph+ALL. A number of Phase II trials have shown activity of this agent to various solid tumors including breast and lung cancer. Imatinib showed activity in thymomas, thus the rationale for using Dasatinib in the treatment of our patient.
Effects of 5-Bromotetrandrine and Daunorubicin on the Expression of Survivin In K562/AO2 Cells
Authors: Chen Bao-An , Cai Xiao-hui , Wang Jun , Gao Chong , Ding Jia-hua , Cheng Jian , Sun Yun-yu , Song Hui-hui , Bao Wen , Chen Ping-shen , Zhang Yu , Tang Meng 
Published: October 2019

Abstract
Abstract 4947

Objective:
The aim of this study was to investigate the expression of survivin and the apoptosis induced by DNR and BrTet in the leukemic cells K562/A02.

Methods:
In a typical experiment, the K562/AO2 cells were treated with daunorubicin (DNR), 5-bromotetrandrine (BrTet), or DNR and BrTet for 48 hours, and the cells treated without any drugs were used as control group. Cell proliferation was analyzed by MTT assay. Cells apoptosis and the concentration of DNR within the cells were measured by Flow cytometry (FCM). The expressions of mRNA and protein of survivin were determined by semi-quantitative reverse transcription PCR (RT-PCR) and Western blot, respectively.

Results:
The results of MTT assay indicated that DNR and BrTet were both able to inhibit the proliferation of K562/AO2 cells in dose-dependent manner. The fresh evidence from flow cytometry showed that a higher apoptosis rate could be induced and a higer concentration of DNR could be detected in K562/AO2 cells by DNR and BrTet as compared with those by DNR or BrTet in the same concentrations(P<0.01). RT-PCR revealed that the expression of survivin mRNA, a higer expression in K562/AO2 cells with acquired resistance to adriamycin than that in parent K-562 cells, decreased in the DNR and BrTet group (P<0.05), but there was no obvious change in other groups(P>0.05). Western bolt demonstrated that the expression of survivin protein was much lower in the DNR and BrTet group(P<0.05).

Conclusion:
BrTet could increase the concentration of DNR and reverse the multidrug resistance(MDR) in the K562/AO2 cells. Survivin may play an important role in apoptosis induced by DNR. Survivin could be a target for the treatment of MDR in haematopoietic malignancies.

Disclosures:
No relevant conflicts of interest to declare.
Reduction of Imatinib Concentration After Gastric Bypass Surgery
Authors: Liu Hongtao , Artz Andrew S 
Published: October 2019

Abstract
Abstract 4948
Imatinib mesylate is an orally bioavailable inhibitor of several protein tyrosine kinases, including BCR-ABL, which was approved for BCR-ABL–positive CML. This oral agent has approximately 98% oral bioavailability independent of a meal, and it is eliminated by biliary excretion and hepatically metabolized. Better clinical outcomes have been associated with higher steady state imatinib trough levels for both CML and GIST. Because imatinib is absorbed, excreted, and possibly recycled in the gastrointestinal tract, gastrointestinal disorders impairing absorption may hinder achieving therapeutically effective imatinib levels. We present the case of a woman with CML who underwent biliopancreatic diversion with duodenal switch for weight loss leading to a marked reduction in imatinib concentration, and as a consequence, inadequate suppression of her CML. This is a 54 year old obese African American woman who achieved complete hematological remission (CHR), and complete cytogenetics remission (CCyR) and good molecule response with a BCR-ABL/c-ABL ratio of 0.015 (1.5%) with close to therapeutic imatinib trough level at 965 ng/mL prior to gastric bypass surgery on imatinib 400mg daily. The patient underwent laparoscopic biliopancreatic diversion with duodenal switch, concomitant cholecystectomy, and appendectomy. Her adjusted imatinib steady state trough level declined to 166ng/mL, 17% of the pre-surgery level and below the concentration required to suppress BCR-ABL activity leading to a 0.5 log increase in BCR-ABL/c-ABL ratio of 0.083 (8.3%). Escalation of imatinib to 400 mg BID led to imatinib trough level of 734 ng/mL and decrease of BCR-ABL/c-ABL ratio to 0.024 (2.4%), a value comparable to the ratio achieved while on imatinib 400mg daily prior to the gastric bypass surgery. Eventually, our patient lost almost 50kg (close to 45% of her original weight) within a year period. Interestingly, the imatinib level increased to 2124 ng/mL on imatinib 400mg twice a day after the substantial weight loss, supporting the correlation of imatinib level and actual body weight. Her PCR BCR-ABL/c-ABL from peripheral blood still revealed a ratio of 0.072 (7.2%) with high therapeutic imatinib level, and a secondary generation TKI, nilotinib, was initiated at 400mg twice a day. The detail of the clinical course was listed in table below.

Disclosures:
No relevant conflicts of interest to declare.
Biologic Features and Clinical Outcomes According to Age Groups In Myelodysplastic Syndrome
Authors: Lee Seungbum , Lee Je-Hwan , Lee Jung-Hee , Kim Dae-Young , Kim Sung-Doo , Lim Sung-Nam , Choi Yunsuk , Park Young-Hoon , Seol Miee , Lee Young-Shin , Kang Young-Ah , Jeon Mijin , Lee Kyoo-Hyung 
Published: October 2019

Abstract
Abstract 4963
Myelodysplastic syndrome (MDS) is a disease of the elderly, but can also affect younger people. Age is known to be an important prognostic factor in MDS but age variable is not included in most prognostic scoring systems because it is not thought as a disease-related variable. Many reports have showed that MDS is seen one to two decades earlier in Far Eastern countries than Western countries. We retrospectively investigated the differences in biologic features and clinical outcomes according to different age groups in Korean patients with MDS. Primary end points of our study were overall survival (OS) and progression-free survival (PFS). PFS was defined as time from diagnosis to AML progression or death. About one third of the patients received intensive treatment including chemotherapy, hypomethylating treatment or hematopoietic cell transplantation. Therefore, all survival data were censored at the start of intensive treatment to eliminate the influence of the treatments on clinical outcomes. A total of 403 patients, 248 males and 155 females, were included in this study. Median age was 54 years. We divided the patients into three age groups: ≤50 years (n=181), 51 to 60 (n=81), and over 60 (n=141). Baseline biologic features were significantly different according to three age groups: with increasing age, more male preponderance (P=0.009), more BM blast percentage (P<0.001), more advanced WHO subtype (P<0.001), higher proportion of high risk cytogenetic features (P=0.052; ≤60 vs. >60, P=0.011), poorer ECOG performance status (P=0.004), higher IPSS risk group (P=0.019). Five-year survival probabilities were significantly different according to age groups (≤ 50 vs. 51–60 vs. > 60; OS, 66.8% vs. 28.5% vs. 12.2%, P<0001; PFS, 58.5% vs. 37.9% vs. 12.3%, P<0.001). Survivals were also significantly different according to age groups in both IPSS Low/INT-1 (P<0.001 for OS, P=0.001 for PFS) and IPSS INT-2/High risk group (P=0.026 for OS, P=0.069 for PFS). Cox proportional hazards models also demonstrated that age group was an independent prognostic factor for survivals: ≤ 50 vs. 51–60 and > 60; OS, RR 2.3 (P=0.037) and RR 4.6 (P<0.001); PFS, RR 1.3 (P=0.449) and RR 2.0 (P=0.012).

Conclusion:
Biologic features and clinical outcomes were significantly different among age groups in MDS. Clinical outcomes were better in younger age group independently of biologic features. Survivals (OS & PFS) were better in younger age group and survival differences by age groups were observed in both lower and higher risk MDS, suggesting that age stratification should be considered in treatment decision and clinical trial design.

Disclosures:
No relevant conflicts of interest to declare.