bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bone Marrow-Derived Adipocytes Promote Differentiation, Proliferation and Survival of Acute Monoblastic Leukemia Cells
Authors: Jin Linhua , Tabe Yoko , Konopleva Marina , Andreeff Michael , Ohsaka Akimichi , Miida Takashi 
Published: October 2019

Abstract
Abstract 1501
Acute monoblastic leukemia occurs most commonly in young individuals, whereas acute monocytic leukemia is common in adults (WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues, 2008). Adipocytes are the prevalent stromal cell type in adult bone marrow (BM) and play an important role in the leukemic bone marrow microenvironment (Tabe et al., Blood 2004 103: 1815–22). BM stromal cells (MSCs) from elderly subjects have a reduced capacity to differentiate into osteoblasts and an increased capacity to differentiate into adipocytes, which leads to progressive accumulation of fat in the BM space with increasing age. In this study, we examined whether BM-derived adipocytes participate in the molecular events associated with proliferation, differentiation and apoptosis of monoblastic leukemia cells. To this end, we performed gene expression microarray analysis of 339 genes associated with lipid metabolism (GeneSQUARE, Kurabo, Japan) using RNA from monoblastic leukemia cell line U937 co-cultured with MSC or MSC-derived adipocytes. Five genes were upregulated (>2.0 fold) and 2 genes down-regulated in U937 cells co-cultured with adipocytes compared to U937 cultured alone. The up-regulated genes included monocyte/macrophage differentiation specific genes, such as scavenger receptor CD36, adipsin or fatty acid binding protein 4 (FABP4). CD36 and FABP4 are classical target genes of PPARγ which was also upregulated in U937 co-cultured with adipocytes. Upregulation of the inflammation-related haptoglobin gene was observed in U937 cells co-cultured with either adipocytes or MSC. These findings were confirmed by quantitative RT-PCR assay with concordant results. Down-regulated genes included monocyte chemoattractant protein-1 (MCP-1) (0.1 fold) and glycolytic enzyme hexokinase 2 (0.4 fold). In turn, U937 cells co-cultured with premature or mature adipocytes accumulated in G2 cell cycle phase compared to U937 cultured alone or co-cultured with MSC (% G2/M-phase fraction; U937 cultured alone, 14.6, co-culture with MSC 25.1, co-culture with preadipocyte 32.0, with mature adipocyte 31.9) and were protected from spontaneous cell death under serum-starved conditions (% subG1 fraction: U937 cultured alone 23.9%, co-cultured with MSC 15.7%, with preadipocytes 3.9% and with mature adipocytes 11.6%). In summary, results suggest that BM adipocytes, abundant in adult BM space, promote monocytic differentiation, proliferation and survival of monoblastic leukemia cells. We propose that these cells represent an essential component of the BM microenvironment that contributes to malignant phenotypes of adults with monocytic leukemia.

Disclosures:
No relevant conflicts of interest to declare.
The Role of Endogenous Stromal Cell-Derived Factor-1 in the Survival and Growth of Acute Myeloid Leukemia Cells
Authors: Kim Ha-Yon , Oh Yoon-Suk , Song Ik-Chan , Lee Hyo-Jin , Yun Hwan-Jung , Kim Samyong , Jo Deog-Yeon 
Published: October 2019

Abstract
Abstract 1502
Stromal cell-derived factor-1 (SDF-1) is constitutively expressed and produced by stromal cells in the bone marrow (BM). The protein exerts its functions by binding to its receptor CXCR4, thus guiding the homing of hematopoietic stem/progenitor cells and leukemia cells to the BM. CD34+ cells purified from normal adult peripheral blood have been shown to express and produce SDF-1, which exerted an antiapoptotic effect on CD34+ cell through an autocrine/paracrine loop. Acute myeloid leukemia (AML) cells have also been shown to express and produce SDF-1, but the role of SDF-1 in this context is largely unknown. Thus, the aim of the present study was to determine the function of SDF-1 produced by AML cells. Using siRNA technology, SDF-1 was knocked-down in AML cells and subsequent biological alterations occurring in the cells were evaluated in vitro. All AML cell lines used in this study (U937, K562, KG1a, HL-60 and MO7e) as well as primary CD34+ cells obtained from the BM of 5 patients with AML expressed SDF-1 mRNA at various levels, as revealed by semi-quantitative and real time RT-PCR analysis. SDF-1 was detected by Western blotting analysis and ELISA allowed for the detection of SDF-1 in the supernatants of cultures of AML cells grown for 3 days in a serum-free medium, indicating that AML cells, similar to normal CD34+ cells, are able to produce and secrete SDF-1. Exogenous SDF-1 (added at a concentration of up to 200 ng/mL) alone had no discernible effects on the survival or proliferation of either the cell lines or the primary CD34+ AML cells maintained in a serum-free medium, but was able to induce the internalization of CXCR4 and CXCR7. Transfection of five AML cell lines with SDF-1 siRNA diminished the SDF-1 mRNA levels by up to 90%. The knock-down cells were stable for at least 3 days. SDF-1 knock-down did not affect the serum deprivation-induced apoptosis of the cells. Cell surface expression of CXCR4 was not changed, whereas cytoplasmic CXCR4 was significantly upregulated along with the upregulation of SDF-1 mRNA. Neither cell surface nor cytoplasmic expression of CXCR7 was affected by the knock-down of SDF-1. Conversely, the knock-down of CXCR7, but not CXCR4, upregulated the SDF-1 mRNA expression in the transfected cells. No changes in the transmembrane and trnasendothelial migration of the knock-down cells were observed. In contrast, the knock-down of SDF-1 inhibited the spontaneous proliferation of the U937, K562, and KG1a cells by 20–30% during a 3-day incubation in a serum-free medium. These results indicate that endogenous SDF-1 of AML cells functions as an autocrine growth factor.

Disclosures:
No relevant conflicts of interest to declare.
R-CHOP21 Vs R-CHOP14 in Diffuse Large B-Cell Lymphoma Patients: Results From a Multicentre Retrospective Study
Authors: Rigacci Luigi , Fabbri Alberto , Puccini Benedetta , Orciuolo Enrico , Pietrini Alice , Iovino Lorenzo , Petrini Mario , Lauria Francesco , Bosi Alberto 
Published: October 2019

Abstract
Abstract 1626
Diffuse large B cell lymphoma (DLBCL) is one of the most common types of non-Hodgkin's lymphoma. R-CHOP21 (C21) is considered the standard therapy but a large number of studies tested R-CHOP14 (C14).
The aim of our study was to evaluate retrospectively a cohort of patients (pts) treated with C21 or C14.
All pts with diagnosis of DLBCL or follicular grade IIIb lymphoma, treated with curative intent were accrued.
From January 2002 to December 2010, 123 pts were treated with C21 and 142 were treated with C14. The median age was 63 (range 19–89). The two cohorts of pts were balanced for all clinical characteristics a part for age (<65 or >64 years) with more aged pts in C21 arm (p 0.000), PS with more advanced PS (2–3) in C21 arm (0.000) and LDH value which was more frequently elevated in C14 arm (p: 0.002). After induction therapy 190 pts (71%) obtained a complete remission: 82/123 (67%) after C21 and 108/142 (75%) after C14. After a median period of observation of 31 months 81 pts relapsed, 42 (51%) in the C21 arm and 39 (36%) in the C14 arm. Considering the two therapies, C21 vs C14, no differences were reported in OS, PFS and DFS: 61% vs 68%, 59% vs 58% and 74% vs 61% respectively. In univariate analysis OS was lower in older pts (p: 0.02), advanced stage (p: 0.02), symptomatic disease (p: 0.05), elevated LDH (p: 0.001), bone marrow infiltration (p: 0.02) and intermediate or high risk IPI (p: 0.000); PFS was lower in advanced stage (p: 0.002), symptomatic disease (p: 0.009), elevated LDH (p: 0.001), bone marrow infiltration (p: 0.001) and intermediate high risk IPI (p: 0.000). In multivariate analysis OS was significantly better in low-intermediate IPI risk pts (p: 0.000) and in pts treated with C14 (p: 0.02); the PFS was better in low-intermediate IPI risk pts (p: 0.000). Considering only pts with low or low-intermediate IPI we observed that OS was significantly superior in the group treated with C14 (90% vs 64% p: 0.03), moreover in young pts (< 65 years) OS was better in pts treated with C14 (81% vs 58% p: 0.05). As expected hematological grade III/IV toxicity was more frequent in pts treated with C14, all pts but three (2%) completed the therapy without delay or dose reduction. No differences in extra-hematological toxicity were observed.

Conclusions:
In conclusion our results confirm that C14 do not improve the results of the standard C21 in the whole lymphoma population but in a subset of pts, young and low/intermediate risk pts, the C14 scheme seems to improve the OS. We will enlarge the cohort of studied patients but further prospective randomized studies are needed to verify this preliminary observations.

Disclosures:
No relevant conflicts of interest to declare.
Hematopoietic Stem Cell Gene Therapy with Lentiviral Vector in X-Linked Adrenoleukodystrophy
Authors: Aubourg Patrick , Hacein-Bey-Abina Salima , Bartholomae Cynthia , Schmidt Manfred , Kutschera Ina , Vidaud Michel , Dal-Cortivo Liliane , Mahlaoui Nizar , Frange Pierre , Bellesme Céline , Lefrère Francois , Dufayet Gaelle , Fischer Alain , van Kalle Christof , Cavazzana-Calvo Marina , Cartier Nathalie 
Published: October 2019

Abstract
Abstract 163FN2
The most severe form of X-linked adrenoleukodystrophy (ALD) is characterized by rapidly progressive and lethal cerebral demyelination in childhood. The progression of cerebral demyelination of ALD can be arrested by allogeneic hematopoietic stem cell (HSC) transplantation (HCT) within 12–18 months, provided the procedure is performed at an early stage of the disease. The long term beneficial effects of HCT in ALD are likely due to the progressive turn-over of brain microglia that are derived from myeloid progenitors in the bone-marrow. Despite the increased availability of cord blood, not all boys with cerebral ALD and who are candidate for HCT have a suitable HLA-matched donor. In addition, allogeneic HCT remains associated with significant mortality risk. In late 2009, we reported that HSC gene therapy with lentiviral vector was able to arrest the progression of cerebral ALD in two boys who have no HLA-matched donor to perform HCT. ALD protein expression in myeloid and lymphoid lineages as well as the identification of identical lentiviral insertion sites in myeloid and lymphoid lineages strongly suggested that multi-potent long-term repopulating hematopoietic cells were transduced. In those 2 treated patients, hematopoiesis has remained polyclonal without evidence of clonal skewing or dominance up to the last follow-up. Data on clinical efficacy, gene marking and lentiviral integration studies with a longer follow-up (4 years ½) will be presented. HSC gene therapy however failed to arrest the progression of cerebral ALD in a third treated ALD patient, 36 months after gene therapy. Hematopoiesis remained also polyclonal in this patient and biological data that could explain failure of gene therapy in this patient will be presented. At last, data on a fourth patient who has been treated more recently (12 months) by HSC gene therapy will also be presented.

Disclosures:
No relevant conflicts of interest to declare.
Cyclin D1 Over-Expressing Mantle Cell Lymphoma Cells Are Hypersensitive to Inhibition of Fatty Acid Synthase (FASN)
Authors: Dengler Michael A. , Gutekunst Matthias , Kopacz Stephanie , Horn Heike , Hofmann Ute , Schwab Matthias , Ott German , van der Kuip Heiko , Aulitzky Walter E. 
Published: October 2019

Abstract
Abstract 1656
Mantle cell lymphoma (MCL) is an aggressive type of B-cell lymphoma characterized by a t(11;14)(q13;q32) chromosomal translocation resulting in a constitutive over-expression of cyclin D1. Cyclin D1 is a multifunctional protein not only regulating cell cycle progression but also affecting other cellular functions including glucose and lipid metabolism. In this study, we investigated the effects of the fatty acid synthase (FASN) inhibitors orlistat and C75 on viability of different MCL cell lines including JEKO-1, MINO, Granta-519, JVM-2, and Rec-1. In all cell lines inhibition of FASN alone induced apoptosis. In contrast, normal peripheral blood lymphocytes were resistant to these compounds.
This proapoptotic effect was dependent on cyclin D1 as silencing of cyclin D1 partially rescued cells from induction of cell death following FASN inhibition. Inhibition of FASN led to a strong induction of the proapoptotic protein NOXA (PMAIP) in all MCL cell lines investigated independent of the p53 status. Pre-treatment of cells with NOXA siRNA significantly reduced induction of cell death demonstrating the predominant role of this proapoptotic protein for the observed effects.
We then analyzed the combined effects of inhibition of FASN with a panel of compounds with potential clinical relevance. Combination of FASN inhibitors with the BH3 mimetic ABT737, the proteasome inhibitor Bortezomib, and the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) led to an almost complete loss of viability. These combinatory effects were selective for MCL cells as the same treatments had almost no effects on cell viability of primary PBMCs or fibroblasts from healthy donors. Bortezomib, 2-DG, and ABT737 enhanced the proapoptotic effect of FASN inhibitors by further disturbing the balance of pro- and antiapoptotic Bcl-2 family proteins: FASN inhibitor mediated induction of NOXA was enhanced by Bortezomib whereas 2-DG significantly reduced the NOXA antagonist Mcl-1.
In summary, our results suggest that FASN inhibitors exert significant antitumoral activity especially in combination with Bcl-2 family modulators in different MCL cell lines and may therefore represent an attractive model for the design of new therapeutic approaches for this entity.

Disclosures:
No relevant conflicts of interest to declare.
Loss of EGR-1 Accelerates BCR-ABL-Driven Leukemogenesis
Authors: Maifrede Silvia , Sha Xiaojin , Liebermann Dan , Hoffman Barbara 
Published: October 2019

Abstract
Abstract 1671
Chronic Myelogenous Leukemia (CML) is a disease resulting from the neoplastic transformation of hematopoietic stem cells (HSC) by the translocated tyrosine kinase BCR/ABL. The BCR-ABL protein product is a constitutively active tyrosine kinase, which promotes cell survival and proliferation by means of diverse intracellular signaling pathways, thereby being the culprit for malignant transformation. The early growth response (Egr)-1 gene, a member of the Egr family of genes encoding for zinc-finger transcription factors, has been shown to be an early response gene, to mediate cellular responses to growth factors and to be a stress response gene. Both growth factor stimulation and stress in most cells causes rapid induction of Egr-1 within minutes that leads to the activation of downstream growth pathways in normal cells. Egr-1 regulates the expression of multiple genes, either directly or indirectly, that impact on cell cycle arrest, survival and/or apoptosis, which can interface with BCR-ABL signaling. Included among these genes are p53, TGFbeta, PTEN, gadd45a, gadd45b, Foxo3a, p21, FasL, and Trail.
There is a large body of evidence consistent with Egr-1 behaving as a tumor suppressor in hematopoietic cells, both in vivo & in vitro, in both humans & mice. This laboratory has shown that Egr-1 abrogates the block in M1 terminal differentiation imparted by either oncogenic c-Myc or E2F-1, suppressing their leukemia promoting function in nude mice. Since Egr-1 can be a tumor suppressor and its down-stream effectors cross-talk with BCR-ABL signaling it was asked if Egr-1 can act as a suppressor of BCR-ABL driven leukemogenesis. To assess the effect of Egr-1 on BCR-ABL driven leukemia, syngeneic wild type lethally irradiated mice were reconstituted with wild type or Egr-1 null myeloid progenitors transduced with a 210-kD BCR-ABL-expressing MSCV-retrovirus. It was observed that loss of Egr-1 accelerated the development of BCR-ABL driven leukemia in recipient mice. In vitro proliferation assays have shown enhanced proliferation capacity for BCR-ABL transduced Egr-1 null myeloid progenitors compared to wild type counterparts. In addition, flow cytometric analysis of Egr-1 null myeloid progenitors from bone marrow (BM) has shown a slightly smaller stem cell (Lineage- Sca+ and c-Kit+ [LSK]) population as compared to wild type progenitors from BM. Therefore, the accelerated induction of BCR/ABL-mediated leukemia using Egr-1 null progenitors cannot be accounted for by increased numbers of stem cells. Taken together, these results indicate that Egr-1 functions as a suppressor of BCR-ABL driven CML. Further elucidating the role of Egr-1 in the murine model of BCR-ABL driven leukemia and analysis of Egr-1 expression in human CML peripheral blood and BM could result in novel targets for diagnosis and prognosis, as well as for targeted therapeutics.

Disclosures:
No relevant conflicts of interest to declare.
Home Azacitidine Administration in High Risk Myelodysplastic Syndromes: Favorable Results of a Pilot Study in 48 Patients
Authors: Guillevic Sylvestre , Comont Thibault , Khalifa Jonathan , Recher Christian , Adoue Daniel , Ollier Sylvie , Cougoul Pierre , Laurent Guy , Beyne-Rauzy Odile 
Published: October 2019

Abstract
Abstract 1719

Background:
Myelodysplastic syndromes (MDS) affect elderly patients. Azacitidine represents the gold standard treatment of high risk MDS. French health organization allows home chemotherapy administration after the first cycle of treatment. We decided to develop a home administration program of this drug. Moreover we hypothesized that this modality of treatment will improve patient's quality of life.
Patients and methods: after one cycle in hospitalization, high risk MDS patients who were agree to receive home chemotherapy were included in the study. As recommended each first day of Azacitidine cycle was still administrated at hospital. Due to drug instability a quality statement was created to control all steps of administration (including storage temperature before administration). Feasibility and safety were evaluated. Comparison between home or hospital administration was performed: number of cycles, dose, tolerance, problems of administration.

Results:
68 patients were included in the home chemotherapy program, 75% were MDS patients and 48 received Azacitidine. Age distribution was 7 patients 60/69 yrs (14%), 22 patients 70/79 yrs (46%) and 19 patients 80–89 yrs (40%). More than 2000 days of hospitalization were performed at home during a 18-month period. Similar median number of cycles and delays were observed in the two groups as well as same level of adverse events and hospitalizations between 2 cycles. In few cases administration was not possible at home due to unresolved infection, cytopenia or drug availability (excessive time between preparation and distribution). No patient was excluded of this program.
Discussion and conclusion: home administration of Azacitidine was safe and feasible. All patients agree to continue this modality of administration and high level of satisfaction was observed. Next step will consist in a randomized study to compare quality of life between home and hospital administration of the drug. For this population of patient home treatment will represent an alternative which could improve quality of life as observed for children in ALL (1) or in colorectal cancer (2).

Disclosures:
No relevant conflicts of interest to declare.
Autocrine IL-6 Production Indicates the Level of Activated STAT3 and NF-Kb of Chronic Lymphocytic Leukemia Cells
Authors: Liu Fengting , Jia Li , Farren Timothy W , Gribben John G. , Agrawal Samir G 
Published: October 2019

Abstract
Abstract 1784
Interleukin-6 (IL-6) is a multifunctional cytokine that plays an important role in survival, apoptosis and proliferation of cancer cells. Previous studies have shown that IL-6 levels are significantly elevated in most cancer cells, while elevated serum levels of IL-6 correlated with adverse prognostic features and shorter survival in patients with chronic lymphocytic leukemia (CLL). IL-6 production is controled by transcription factors NF-kB and STAT3, which are themselves controled by tyrosine kinase phosphorylation, such as that mediated by JAK2. This creates a positive feedback loop, as JAK2 can be stimulated by IL-6.
In this study we investigated the relationship between autocrine IL-6 production and activation of STAT3 and NF-kB in CLL patients. The levels of IL-6 production in cell culture medium were measured by ELISA and activation of STAT3 and NF-kB was indicated by the ratio of p-STAT3/STAT3 and p-NF-kB/NF-kB. Patients with high levels of p-STAT3/STAT3 and/or p-NF-kB/NF-kB had higher levels of IL-6 production. The level of IL-6 production significantly correlated with STAT3 activation (R=0.856, p < 0.001) and NF-kB activation (R=0.815, p < 0.001). Inhibition of constitutive STAT3 and NF-kB activation by the STAT3 phosphorylation inhibitor, DPP, and the NF-kB inhibitor, CAPE, blocked IL-6 production 40% in average (p = 0.004, p = 0.003). Analysing the level of autocrine IL-6 production and in vitro spontaneous apoptosis in CLL cells from 38 patients, we found that patients with higher levels of IL-6 production (more than median) had significantly less apoptosis compared with those below the median (23% vs. 42.2% in average, p <0.0001). In this cohort, 60% of CD38+ cases, 78% of 17p- cases and 67% of cases with a lymphocyte doubling time of less than12 months were in the high IL-6 producer group. High IL-6 production was also associated with a shorter average time to first treatment (0.5 vs. 3 years, p=0.0023).
This study demonstrates that autocrine IL6 production correlates with STAT3 and NF-kB activation and apoptosis resistance in CLL. Furthermore, higher IL-6 production is associated with biological markers of poor prognosis and earlier treatment. The IL6/JAK2/STAT3 signal pathway may offer new therapeutic targets for CLL.

Disclosures:
No relevant conflicts of interest to declare.