bluuebunny/crossref_metadata_2025_split huggingface dataset:
“An Intention-to-Treat Analysis of Rome Transplant Network Policy for Alternative Donor Search in Patients Lacking a HLA Matched Related donor”.
Authors: Picardi Alessandra , de Fabritiis Paolo , Dentamaro Teresa , De Rossi Giulio , Caniglia Maurizio , Pinto Rita , Petti Maria Concetta , Mengarelli Andrea , Annino Luciana , Chierichini Anna , Monarca Bruno , Montefusco Enrico , Avvisati Giuseppe , Tirindelli Maria Cristina , Mangione Ilaria , Cudillo Laura , Cerretti Raffaella , De Angelis Gottardo , Di Veroli Ambra , Arcese William 
Published: October 2019

Abstract
Abstract 1195
Poster Board I-217
The policy of the Rome Transplant Network (RTN), a metropolitan network of transplant Centers, for patients candidates to an allogeneic hematopoietic stem cell transplant (HSCT) and lacking an HLA identical sibling is the contemporary search for one the HSC alternative sources such as Matched Unrelated Donor (MUD),Cord Blood Unit (CBU) or Haploidentical Related Donor (HRD). The main aim of the RTN policy is the identification of a suitable donor in order to perform transplant in adequate timing. The selection criteria for MUD consist of a 8/8 HLA loci matching tested at low resolution for class I HLA and at high resolution (HR) for class II; one difference in C Ag is considered acceptable in case of both I and II class HR identity. CBU's selection criteria are instead based on cell doses (TNC≥2.5×107/kg and CD34+≥1× 105/kg) and on a HLA-compatibility ≥to 4/6 HLA Ag. From April 2006, the haplodentical option was also simultaneously considered, so all closer family members have been tested for the HLA. Here, we report the results of the intention to treat (ITT) analysis on the potential therapeutic impact of our transplant policy. Data were obtained from RTN database. From April 2006 to date, 196 pts have been candidated to receive an allogeneic HSCT for hematological disease. Sixty-six out of 196 (34%) underwent HSCT from HLA identical sibling, while a search process for an alternative donor was activated for 130 pts. Of 130 pts, 9 (7%) lost the eligibility to transplant early during the search process and 19 (15%) died of early disease progression in most cases: a suitable MUD or CBU had been identified for 13 of 19 within 3 months from the start of the search and only 6 pts (5%) died without an alternative donor had been found. To date, 73/102 evaluable pts (72%) lacking an HLA identical sibling have been transplanted (n=66: 23 MUD; 24 CBU; 19 HRD) or are willing to proceed towards the transplant (n=7: 3 MUD;2 CBU; 2 HRD). In summary, for all 196 candidates to an allogeneic transplant the eligibility was confirmed for 187 (95%), a suitable donor could be identified for 181 (92%) of all pts or 97% of the eligible ones and an allogeneic transplant could be performed for 168 (86%) of all candidates or 93% of those eligible. From this ITT analysis, we can conclude that, by adopting the RTN policy of widespread donor search and multiple transplant options, the allogeneic transplant can be offered as potential therapeutic procedure to a large majority of pts.

Disclosures:
No relevant conflicts of interest to declare.
ON 01910.Na Suppresses Cyclin D1 Accumulation in trisomy 8 Myelodysplastic Syndromes Patients While Decreasing Bone Marrow CD34+ Blast Counts and Aneuploid Clone Size.
Authors: Sloand Elaine M , Olnes Matthew J. , Galili Naomi , Shenoy Aarthi , Pfannes Loretta , Wilhelm Francois , Weinstein Barbara , Scheinberg Phillip , Groopman Jerome E. , Raza Azra 
Published: October 2019

Abstract
Abstract 120

Patients with high risk MDS can be successfully treated with 5-azacytidine, or with lenalidomide but non-responding patients have few treatment options. Chemotherapy produces significant morbidity and very short remissions and most patients are too old for bone marrow transplantation. We previously demonstrated up-regulation of c-myc, survivin, and cyclin D1 in CD34+ cells in patients with trisomy 8 (and selected patients with monosomy 7). siRNA-mediated knockdown of survivin or c-myc decreased trisomy 8 cell growth in vitro (Sloand et al, Blood 2007, 110: 822). We postulated that increased cyclin D1 causes upregulation of survivin, resulting in resistance of these cells to apoptosis. The styryl sulfone, ON 01910.Na, decreases cyclin D1 accumulation in cultured bone marrow from patients with high risk trisomy 8 MDS and in some monosomy 7 patients (who also show upregulation of cyclin D1), while selectively decreasing blasts and aneuploidy with this cytogenetic abnormality (ASH Abstracts Nov 2008; 112: 1651). Here we examine the clinical response to ON1910 in an ongoing phase I/II clinical trial in which 13 evaluable patients with intermediate-1(int-1) to high risk MDS and treatment-refractory trisomy 8 AML were enrolled. Patients were treated with escalating doses of ON 01910.Na at 800 mg/m2 × 2 days every 3/4 weeks, 800 mg/m2 × 3 days every 2 weeks, 800 mg/m2 × 5 days every 2 weeks, and 1500 mg/m2 × 2 days every 3/4 weeks at two institutions. No significant toxicity could be ascribed to the drug. Patients with trisomy 8 and monosomy 7 demonstrated significant declines in aneuploidy measured by florescence in situ hybridization (FISH) (mean aneuploidy; 50% before and 24% after 1 cycle of treatment; p=0.02 :Fig below). Rather than becoming cytopenic, many patients showed substantial improvements of blood counts and one patient (01-02; graphic shown below) became red cell transfusion-independent and maintains his remission 14 months after stopping therapy. Cyclin D1 measurement by flow cytometry showed decreases of this protein in both CD34 and CD33 cells during infusion of ON 1910 infusion (example shown in Fig below). Results from individual evaluable patients are shown in table 1. These results indicate that modulation of cell cycle control by cyclin D1 may represent a novel targeted approach for trisomy 8 and monosomy 7 MDS.

Disclosures:
Sloand: Onconova: Research Funding. Olnes:Onconova: Research Funding. Galili:Onconova: Research Funding. Wilhelm:Onconova: Employment. Groopman:Onconova: Membership on an entity's Board of Directors or advisory committees. Raza:Onconova: Research Funding.
Infusion of Large Number of Circulating Myeloma Cells Does Not Influence the Survival of Patients Undergoing Autologous Stem Cell Transplantation.
Authors: Abonour Rafat , Knollman Hayley , Suvannasankha Attaya , Yu Menggang , Britton Rebecca , Srivastava Shivani , Nelson Robert P. , Schwartz Jennifer E. , Robertson Michael , Cornetta Kenneth , Farag Sherif 
Published: October 2019

Abstract
Abstract 1224
Poster Board I-246
Multiple myeloma (MM), is a monoclonal plasma cells disorder that constitutes 10% of all hematologic malignancies. Patients with a good performance status are usually offered high-dose therapy (HDT) followed by autologous stem-cell transplantation (ASCT). HDT/ASCT is associated with complete response (CR) rates of up to 40%. Although a significant proportion of patients have a durable response after HDT/ASCT, others relapse relatively quickly and do not appear to benefit from the procedure, which may impact the overall survival (OS) of these patients. We attempt here to define the role of infusing mobilized myeloma cells on the survival of patients undergoing ASCT.

Methods
After obtaining an Institutional Review Board approval, we conducted a retrospective analysis on MM patients undergoing ASCT at our center. Data of disease status, graft characteristics, and outcome were collected. As part of the flow panel used to assess the mobilized ASC, monoclonal myeloma cells were identified by gating on a population of cells that express high levels of CD38 but do not stain or weakly with CD45 (CD38+/CD45−). OS was calculated from the date of ASCT to the time of death or last contact. Survival analysis was performed using the method of Kaplan and Meier (KP). Univariate and multivariate analysis was performed using the Cox proportional hazards model.

Results
349 patients underwent ASCT between January 1999 and April 2008. Complete data on autograft characteristics were available on 303 patients. The mobilization regimen was Cyclophosphamide and GCSF for the majority of the patients and GCSF for the more recent transplants. Melphalan at 200 mg/m2 was give 18 hours prior ASC infusion. In 199 patients there was no CD38+/CD45- cells detected. Among the 104 patients with evidence of CD38+/CD45- cells the range was 0.1-10.2 ×10 6 cells/kg and there was no difference in survival in this patient group compared to the group without evidence of contaminating myeloma cells (p= 0.54). Continuous variable analysis also did not reveal any relationship between the dose of CD38+/CD45- cells and survival (p=0.84). There may be a survival advantage after 40 moths for those receiving CD38+/CD45- cells, however the scientific rational is not well understood. Neither B2 microglobulin nor the numbers of plasma cells in the bone marrow were relevant in multivariate analysis (p= 0.42 and 0.13, respectively).

Conclusion
The presence of myeloma cells in the autograft does not appear to influence overall survival and the inclusion of CD45 and CD38 flow cytometric analysis of mobilized stem cells may not be necessary.

Disclosures
No relevant conflicts of interest to declare.
Overexpression of Rasgrf1, a Guanine Nucleotide Exchange Factor in Chronic Lymphocytic Leukemia.
Authors: Sharma Sanjai 
Published: October 2019

Abstract 1253
Poster Board I-275
We performed microarray expression analysis to identify genes which are differentially expressed in chronic lymphocytic leukemia (CLL) cells. A number of genes from the cohort of maximally upregulated genes were members of the Ras superfamily of proteins function which function as switches between active GTP-complexed and inactive GDP-complexed states. One of the genes upregulated on the microarray analysis in all the CLL cells as compared to normal B cells was RASGRF1. This ras protein specific guanine nucleotide release factor stimulates the dissociation of GDP and activates Ras signaling pathway. To confirm our microarray analysis results, we performed real time PCR analysis on 35 CLL specimens and observed a 10-50 fold upregulation of rasgrf1 RNA as compared to human peripheral blood B cells. This high expression is consistently observed in all CLL specimens regardless of stage indicating that this upregulation is an early important event in the pathogenesis of CLL. Rasgrf1 protein expression was also higher in CLL cells as compared to normal B cells by western blot analysis. Interestingly the rasgrf1 gene is genomically imprinted during development in certain tissues and the expression is downregulated. Demethylation of normal peripheral blood B cells by treatment with azacytidine resulted in increased expression of rasgrf1 with no change in expression of rasgrf1 in CLL cells implying imprinting in normal B cells. Thus malignant transformation of B cells to CLL cells results in a loss of genomic imprinting and an aberrant upregulation of rasgrf1 in CLL cells. One important downstream effect of rasgrf1 upregulation is ERK activation via Ras-MAPK pathway. B cell receptor signaling in CLL results in activation of a number of pro-survival pathways including ERK which is more active in poor prognosis, unmutated immunoglobulin heavy chain CLL. Our results indicate that ERK phosphorylation is also increased in CLL specimens with rasgrf1 overexpression.

Disclosures
No relevant conflicts of interest to declare.
Dasatinib-Induced Apoptosis in Chronic Lymphocytic Leukaemia Is Abrogated by Selective Micro-Environmental Signals.
Authors: McCaig Alison M , Leach Mike , Michie Alison M 
Published: October 2019

Abstract
Abstract 1264
Poster Board I-286

Background
Recent advances in chronic lymphocytic leukaemia (CLL) biology indicate that a plethora of micro-environmental factors are important in promoting the pathogenesis of the disease. As B cell antigen receptor (BCR) signalling plays a critical role in CLL progression, we chose to study the effect of dasatinib, a dual src/abl tyrosine kinase inhibitor, on CLL cells, thus targeting the key, BCR-proximal tyrosine kinases Lyn and c-Abl that are over-expressed in CLL. We were interested to determine the impact of BCR-signalling directed therapy on CLL cell viability in the context of the leukaemic micro-environment.

Results
Clinically relevant concentrations of dasatinib (100 nM) both inhibited ERK-MAPK and Akt phosphorylation, and prevented calcium mobilisation following BCR crosslinking. Furthermore, dasatinib prevented up-regulation of Mcl-1 observed on prolonged BCR stimulation, abrogating the BCR-driven increase in CLL cell survival. Dasatinib induced apoptosis of CLL cells, with a mean reduction in viability of 35.2% ± 3.8% following 48 hr exposure (n=26). Neither ZAP-70 expression nor cytogenetic abnormalities were predictive of response. In addition, dasatinib exhibited synergy with both fludarabine and chlorambucil, with mean ED50 combination indices of 0.29 and 0.62 respectively. Additional micro-environmental elements responsible for the maintenance and progression of CLL include stromal or ‘nurse-like’ cells and activated T lymphocytes, the latter of which express CD40 ligand and secrete IL-4. CLL cell co-culture with the murine bone marrow stromal cell line NT-L significantly inhibited both spontaneous and dasatinib induced apoptosis. As we observed that stromal co-culture significantly increased phosphorylation of both ERK-MAPK and the Akt/mTOR target p70 S6 kinase in CLL cells, we investigated whether pharmacological inhibition these signalling pathways may re-sensitise CLL cells to dasatinib in co-culture. Both the MEK inhibitor PD98059 and PI3K inhibitor LY294002 significantly increased the level of apoptosis observed on dasatinib treatment of CLL cells in stromal co-culture. Dasatinib also retained the ability to potentiate the effects of fludarabine and chlorambucil in stromal co-culture, however, CLL cells co-cultured with NT-L cells stably transfected with CD40 ligand (CD154L cells) were resistant to all drug combinations. Furthermore, on CD154L/IL-4 co-culture, dasatinib failed to prevent up-regulation of Bcl-xL and Mcl-1, or inhibit CLL cell proliferation.

Conclusions:
While dasatinib was capable of reversing BCR-mediated survival signals, it was unable to overcome stromal-derived survival signals, indicating that combination of dasatinib with agents targeting antigen-independent micro-environmental pathways are required to effectively target CLL cells in tissue niches.

Disclosures
No relevant conflicts of interest to declare.
Polycomb Repressor Complex 2 Regulates HOXA9 and HOXA10, Activating ID2 in NK/T-Cell Lines.
Authors: Nagel Stefan , Venturini Letizia , Victor Marquez E. , Meyer Corinna , Kaufmann Maren , Scherr Michaela , MacLeod Roderick A.F. , Drexler Hans G. 
Published: October 2019

Abstract
Abstract 1281
Poster Board I-303
Many oncogenes code for transcription factors involved in regulation of developmental pathways. The activity of these pathways is tissue specific and restricted to certain developmental stages. Here, we searched for T-cell acute lymphoblastic leukemia (T-ALL) oncogenes which physiologically regulate differentiation of natural killer (NK) cells. NK- and T-cells are closely related lymphocytes, sharing the same early progenitors which can differentiate into either lineage. We compared expression profiles of malignant NK- and T-cell lines to identify aberrantly expressed genes in T-ALL. This analysis revealed high expression of HOXA9, HOXA10 and ID2 in NK-cell lines and in one T-ALL line, LOUCY, suggesting leukemic deregulation therein. Subsequently, we analyzed mechanisms underlying their regulation. Overexpression and chromatin immuno-precipitation experiments demonstrated that HOXA9 and HOXA10 directly activate ID2 expression. Analysis of other ALL and acute myeloid leukemia cell lines with and without mixed lineage leukemia (MLL) gene translocations demonstrated a correlated expression of HOXA9/10 and ID2, highlighting ID2 as an indirect target of MLL fusion proteins which deregulate HOXA genes. Furthermore, profiling data of genes coding for chromatin regulators of homeobox genes, including the components EZH2 and HOP of polycomb repressor complex 2 (PRC2), showed downregulation of EZH2 in LOUCY and limited expression of HOP to NK-cell lines. Subsequent treatment of T-ALL cell lines JURKAT and LOUCY with DZNep, an inhibitor of EZH2/PRC2, resulted in elevated and unchanged HOXA9/10 expression levels, respectively, confirming repressive activity of EZH2 in T-cells. Additionally, profiling data and overexpression analysis indicated that reduced expression of E2F cofactor TFDP1 contributed to the lack of EZH2 in LOUCY. Forced expression of HOP in JURKAT cells resulted in reduced HOXA10 and ID2 expression levels, suggesting enhancement of PRC2 repression. Taken together, our results show that major differentiation factors of the NK-cell lineage, including HOXA9, HOXA10 and ID2, were (de)regulated via PRC2 and may contribute to T-cell leukemogenesis.

Disclosures
No relevant conflicts of interest to declare.
Findings of Thrombophilia Evaluation and Impact On Management in Asymptomatic Children with a Proximate Family History of Early Thromboembolism: An Institutional-Based Prospective Inceptional Cohort Study.
Authors: Calhoon Meghan J. , Pounder Elizabeth , Manco-Johnson Marilyn J. , Goldenberg Neil A. 
Published: October 2019

Abstract
Abstract 1289
Poster Board I-311
ABSTRACT

Background and Objective
Although the overall incidence of venous thromboembolism (VTE) is low in children, risk is greatly increased by a proximate family history of early TE. The principal aims of the present study were to determine among such children: (1) the prevalence of thrombophilia; and (2) the frequency of recommended changes in management resulting from thrombophilia evaluation.

Methods
Laboratory thrombophilia investigation was performed in 56 children (≤ 18 years of age) with a first- or second-degree family history of TE before age 55 years, but without personal history of TE, who were consecutively enrolled in an institutional-based prospective inceptional cohort study of pediatric thrombosis/thrombophilia between March 1, 2006 and June 1, 2009. VTE risk factors, family history, thrombophilia findings, and management recommendations were systematically collected.

Results
The frequencies of all thrombophilia traits were higher than expected for the general population; factor V (FV) Leiden, elevated factor VIII activity, elevated lipoprotein(a) concentration, and antiphospholipid antibody positivity were most common (Figure 1). Among 32 children who underwent complete laboratory evaluation, 34% had ≥2 traits (Figure 2). Thrombophilia testing led to a change in recommended management in 71% of subjects, principally consisting of transient anticoagulant prophylaxis during periods of heightened clinical risk for VTE. Furthermore, recommendation against future use of estrogen-containing oral contraceptive pills was made in 32% of females based upon FV Leiden testing alone, as compared to 64% in whom additional laboratory evaluation was performed (P=0.02).

Conclusions
Multi-trait thrombophilia is common among asymptomatic children who have a proximate family history of early TE. In this cohort study, comprehensive thrombophilia testing in such children informed future use of estrogen-containing oral contraceptives among females, and often resulted in a recommendation for antithrombotic prophylaxis during high-risk situations. Future studies should evaluate the safety and efficacy of risk-stratified primary prevention strategies for pediatric VTE.

Disclosures
Manco-Johnson: Baxter BioScience: Honoraria; Bayer HealthCare: Honoraria; CSL Behring: Honoraria; NovoNordisk: Honoraria; Octapharma: Honoraria.
Immune-Modulatory Effects of Mesenchymal Stromal Cell Infusions for the Treatment of Factor VIII Inhibitor in Hemophilia A.
Authors: Matsui Hideto , Harpell Lori , Powell Sandra , Rafei Moutih , Galipeau Jacques , Hough Christine , Lillicrap David 
Published: October 2019

Abstract
Abstract 1299
Poster Board I-321
The current most serious treatment-related complication in hemophilia A is the development of antibodies to FVIII following exposure to FVIII replacement therapy. We have previously demonstrated that the injection of syngeneic mesenchymal stromal cells (MSCs) into hemophilia A mice with FVIII antibodies lead to a robust decrease in FVIII specific IgG levels because the secretome of MSCs suppresses plasma cell immunoglobulin production, induces plasmablast proliferation, and leads to IL-10-mediated blockade both in vitro and in vivo. Therefore, we wanted to pursue this study in a large animal model. In the current study, we harvested MSCs from bone marrow aspirates obtained from 2 hemophilia A dogs with both human and canine FVIII inhibitors. The isolated MSCs were expanded ex vivo for the infusions. Prior to the infusions, we performed in vitro characterization of the canine MSCs and found that the cells secrete a wide range of cytokines and chemokines including CC chemokine ligand 2 (CCL2) and CCL2 that has been cleaved to its truncated inhibitory form by proteolysis with matrix metalloproteinases (MMPs). These results are identical to those seen in the previous mouse experiments. Before the MSC infusions, the hemophilia A dogs with inhibitors were immunized by multiple intravenous infusions of both human FVIII and canine cryoprecipitate to further boost the development of FVIII antibodies. Expanded autologus MSCs (4.5-6.0×106 cells/Kg) were infused intravenously into the first dog twice, with a month in between each injection. After the second infusion, the titer of anti-human FVIII inhibitory activity was significantly decreased from 6.2 to 1.9 BUs and a transient but significant decrease from 3.5 to 2.2 BUs against canine FVIII. Second MSC infusion trial is currently ongoing in a second dog. In parallel with in vivo study, the inhibitory response mediated by MSCs on the FVIII antibody producing B cells was assessed by ELISPOT assay. In conclusion, MSCs may play an immunosuppressive role in modulating Immunoglobulin production by plasma cells via MMP processing of paracrine CCL2 secretion. This may represent a novel cellular therapy for attenuation of pathological humoral responses such as anti-FVIII antibody development.

Disclosures
No relevant conflicts of interest to declare.