bluuebunny/crossref_metadata_2025_split huggingface dataset:
MicroRNAs Are Differentially Expressed Among Cytogenetic Subgroups in Multiple Myeloma.
Authors: Corthals Sophie L , Jongen-Lavrencic Mojca , de Knegt Yvonne , Goldschmidt Hartmut , Lokhorst Henk , Sonneveld Pieter 
Published: October 2019

Abstract
Abstract 2833
Poster Board II-809
Micro-RNAs (miRNAs) are a class of small non-coding single stranded RNAs of 20-22 nucleotides in length. MiRNAs regulate gene expression by binding to the 3' UTR of target mRNAs, which leads to either mRNA degradation or translational inhibition of this target mRNA. MiRNAs play a critical role in cell growth, survival and differentiation and have been suggested to function as tumor suppressor and oncogenes, and/or play a critical role in the pathogenesis of Multiple Myeloma (MM). We investigated miRNA expression in 41 newly diagnosed patients with MM who were included in a clinical trial. MiRNA expression profiling was performed in BM derived CD138 selected plasma cells (PC) obtained from newly diagnosed MM patients with a minimum monoclonal PC purity of > 80%. A quantitative PCR-method (TaqMan low density arrays-microRNA assay', Applied Biosystems) was used for miRNA quantification. The relative expression levels of miRNAs were calculated using the 2-DDCt method and the data was normalized using the endogenous control RNU48. 176/365 miRNAs (48.2%) were expressed in these MM patients. Unsupervised hierarchical clustering based on the average-linkage method and principal component analysis (PCA) was performed in Partek software (Partek Genomics Suite), showing a differential hierarchy for the chromosomal translocation or gain subgroups. When patients with or without chromosome 13 deletions were compared, no correlation was found between expression levels of miRNAs located on chromosome 13 and the deletion status of this chromosome as determined by FISH. Three miRNAs, i.e. miRNA-126, miRNA-145 and miR-517c were identified that were different between MM patients with or without chromosome 13 deletion. These miRNAs were not located on chromosome 13. Likewise, when comparing the miRNA expression in MM patients with or without chromosome 1q gain, the three most differentially expressed miRNAs were miRNA-23a, miRNA-200a# and miRNA-145, which are not on chromosome 1. In addition, miR-18a, located on chromosome 1 was upregulated in MM patients with 1q gain. MM patients with t(4;14) showed differential expression of miRNA-520g, miRNA-28 and miRNA-502. Currently we evaluate potential association of microRNA expression with the clinical response of MM patients to Bortezomib.
In conclusion, our data indicate that miRNAs are differentially expressed in subgroups of MM patients characterized by common cytogenetic abnormalities.

Disclosures:
Goldschmidt: Johnson and Johnson: Research Funding, Speakers Bureau. Sonneveld:Johnson and Johnson: Research Funding, Speakers Bureau.
SIGNIFICANCE of ABSOLUTE LYMPHOCYTE COUNT at RELAPSE as a PROGNOSTIC FACTOR in PATIENTS with T-CELL NON-HODGKIN'S LYMPHOMA.
Authors: Choi Dae Ro , Yoon Dok Hyun , Ahn Heui June , Cho Yoojin , Kim Eun Kyoung , Kim Shin , Huh Jooryung , Lee Dae Ho , Kim Sang We , Lee Jung Shin , Suh Cheolwon 
Published: October 2019

Abstract
Abstract 2939
Poster Board II-915

Introduction:
Peripheral blood absolute lymphocyte count (ALC) at the time of diagnosis is a prognostic indicator in hematologic malignancies. However, no reports have addressed whether ALC at the time of first relapse (ALC-R) has a prognostic significance in the patients with relapsed T-cell Non-Hodgkin's lymphoma (NHL). We retrospectively studied the prognostic significance of ALC-R in these patients.

Patients and Methods:
We identified 63 patients who had a documented relapsed disease after having reached a complete response, including at least an unconfirmed complete response between 1993 and 2007 and we analyzed their ALC-R and following variables at the time of first relapse; age, gender, the number of extranodal sites, lactate dehydrogenase, ECOG performance status, stage and international prognostic index.

Results:
Out of the 63 patients, 23 (36.5%) had a peripheral T-cell lymphoma, not otherwise characterized, while 15 (23.8%) had an extranodal NK/T-cell lymphoma, nasal type, 6 (9.5%) anaplastic large-cell lymphoma, 5 (7.9%) angioimmunoblastic T-cell lymphoma, 2 (3.2%) primary cutaneous T cell lymphoma and 12 (19%) other types. Among them, 32 (50.8%) had an ALC-R ≥ 1.25 × 109/L, 47 (74.6%) had an ECOG PS 0 or 1 and by IPI at relapse, 0, 1, 2, 3, 4, and 5 were 20.6%, 25.4%, 23.8%, 23.8%, 4.8%, and 1.6%, respectively. Univariate analyses showed that good ECOG PS (HR, 0.408; 95% CI 0.190-0.876; p=0.022) and high ALC at relapse (HR, 0.394; 95% CI 0.210-0.740; p=0.004) were associated with longer survival from relapse (Table 1). Multivariate analysis also showed that high ALC at relapse (HR, 0.369; 95% CI 0.187-0.726; p=0.004) and good ECOG PS (HR, 0.295; 95% CI 0.131-0.666; p=0.003) were still associated with longer survival outcome (Table 2).

Conclusions:
The high ALC-R predicted a better prognosis in patients with relapsed T-cell NHL, suggesting that the host immune system might have a crucial role.

Disclosures:
No relevant conflicts of interest to declare.
PTEN Regulates SYK-Directed AKT Activation in MCL.
Authors: Rudelius Martina , Pittaluga Stefania , Sebasigari Denise , Davies-Hill Theresa , Klier Margit , Quintanilla-Martinez Leticia , Fend Falko , Tabe Yoko , Raffeld Mark 
Published: October 2019

Abstract
Abstract 2941
Poster Board II-917
Mantle cell lymphoma (MCL) can be divided into two clinicopathologic subtypes, a common or “typical” form, and an aggressive “blastoid” variant. A subset of MCL, including all of the aggressive blastoid variants, shows constitutive activation of the PI3K/AKT pathway. Since the BCR-associated SYK tyrosine kinase can activate the PI3K/AKT pathway during normal BCR signaling, we wished to assess its role in MCL.
Five MCL cell lines (Granta 519, Rec-1, Jeko, Z138C and JVM-2) and 32 primary cases were studied for SYK activation and phosphorylation of several SYK targets, including blnk and PLC-gamma. The functional role of SYK was assessed by pharmacologic inhibition with R406, Piceatannol and SYK II inhibitor (2-(2-Aminoethylamino)-4-(3-trifluoromethyl-anilino)-pyrimidine-5-carboxamide, Dihydrochloride, Dihydrate). To rule out off target effects functional data was validated by siRNA experiments. Subsequently we analysed the effects of PTEN and constitutively active (S380A) PTEN in 2 cell lines (Granta 519 and Z138C).
All cell lines were found to have constitutively activated SYK accompanied by phosphorylation of its downstream targets blnk and PLC-gamma. Inhibition of SYK with pharmacologic inhibitors or by specific siRNA resulted in AKT inactivation, suggesting a causal relationship between SYK activation and AKT activation in the cell lines. However, all primary MCL cases demonstrated constitutive activation of SYK, regardless of the activation state of AKT. Interestingly, p-AKT expression correlated with PTEN inactivation, as assessed by p-PTEN expression, in both primary cases and MCL cell lines. Increasing PTEN phosphatase activity, by introducing a constitutively active PTEN, abrogated AKT phosphorylation, without affecting SYK activity. These data suggest that SYK activity in MCL is necessary, but not sufficient to activate the PI3K/AKT pathway, and that an additional critical step is the inactivation of PTEN. This study reveals new complexity in the dysregulation of survival pathways in MCL that may be relevant to pathogenesis.

Disclosures:
No relevant conflicts of interest to declare.
Constitutive Activation of Rac GTPases Is Induced by Cooperating Mutations in a Human Model of MLL-AF9 Leukemia.
Authors: Wunderlich Mark , Link Kevin A , Chou Fu-Sheng , Mulloy James C. 
Published: October 2019

Abstract
Abstract 2959
Poster Board II-935
Retroviral transduction of primary human umbilical cord blood CD34+ cells with a gene encoding MLL-AF9 (MA9) efficiently promotes immortalization in vitro and development of leukemia in a xenotransplant model. MA9 cells remain cytokine dependent with a strict requirement for Flt3 signaling. Additionally, the cells are hypersensitive to inhibition of the RAC GTPases. In this current study, we have examined a potential link between these pathways. We found that MA9 cells proliferate in culture media containing Flt3 Ligand (FL) as the sole cytokine, indicating that Flt3 signaling is sufficient for growth and survival. Furthermore, introduction of a mutant Flt3-ITD gene in these cells (MA9-ITD cells) not only promotes cytokine independent growth, but also significantly decreases leukemia latency in xenotransplant experiments. Consistent with the persistent requirement for active Rac signaling, we found that MA9 cells stimulated with FL induce the activated form of Rac (Rac-GTP) while MA9-ITD cells contain constitutively high levels of Rac-GTP, even after serum starvation and in the absence of all cytokines. Interestingly, we found that expression of the activated mutant NRas-G12D in MA9 cells (MA9-NRas cells) also leads to constitutive Rac activation, cytokine independent growth, and decreased leukemia latency upon transplantation into immunodeficient mice. Taken together, these results indicate that RAC activation may be a common integrating pathway by which secondary mutations cooperate in the progression towards leukemia. Consistent with this notion, both MA9-ITD and MA9-NRas cells remain sensitive to Rac inhibition with a small molecule Rac inhibitor or shRNA knockdown of Rac1 or Rac2. These data indicate that Rac signaling remains critical for MA9 survival and proliferation even in the context of additional mutations and highlights the therapeutic potential for targeting Rac.

Disclosures:
No relevant conflicts of interest to declare.
Recurrent Miscarriage in Women with and without Antiphospholipid Syndrome: Prognosis and Predictors of a Subsequent Successful Delivery.
Authors: Cohn Danny M , Middeldorp Saskia , Korevaar Johanna C , Dawood Feroza , Büller Harry R , Goddijn Mariëtte , Farquharson Roy 
Published: October 2019

Abstract
Abstract 2971
Poster Board II-947

Introduction:
Women with antiphospholipid syndrome (APS) are at increased risk of recurrent miscarriage. Remarkably, the outcome of a successive pregnancy in women with APS and recurrent miscarriage is merely unknown.

Patients and methods:
We performed a cohort study including all women with 2 or more consecutive miscarriages who attended the recurrent miscarriage clinic of Liverpool Women's Hospital, Liverpool, UK between 1988 and 2006. All women underwent a systematic diagnostic work up including testing for APS. Women with proven APS (according to the SAPPORO criteria) were studied, and outcomes were compared to women with unexplained recurrent miscarriage. We excluded all women from couples with other reasons for recurrent miscarriage.

Results:
737 women were included, of whom 220 (30%) had APS. Mean age (32 years) and obstetric history (mean number of prior losses: 3) did not differ between women with and without APS. Of women with APS, 148 (67%) had a successful pregnancy outcome as compared to 324 women without APS (63%), OR=1.2 (95%CI 0.9 to 1.7). No differences were found for birth weight, gestational age, and intra-uterine growth retardation. Women with APS who received aspirin and heparin more often had a successful pregnancy 53/67 (79%) as compared to women without treatment 26/44 (59%); OR=2.6 (95%CI 1.0 to 6.6). Combined use of aspirin and heparin was not associated with an increased success rate in women without APS: 25/43 (58%) vs 204/305 (67%); OR=0.7 (95%CI 0.3-1.4).

Conclusions:
The prognosis of a successive pregnancy in women with recurrent miscarriage and APS was comparable to women with unexplained recurrent miscarriage. However, the combined use of heparin and aspirin was associated with a significantly increased chance of a successful pregnancy in women with APS.

Disclosures:
No relevant conflicts of interest to declare.
Elevated Cholinesterase Activity in Patients with TIA and Other Thrombotic Disorders.
Authors: Horstman Larry Lawrence , Ahn Yeon-Soong , Esquenazi Jacob , Jy Wenche , Bidot Carlos J , Ortega Camile 
Published: October 2019

Abstract
Abstract 2991
Poster Board II-967

Background.
The natural function of ACTH in blood is not well defined. However elevated plasma level was reported in patients with chronic inflammation, suggesting as one of inflammatory markers. Erythrocytes possess membrane-bound acetylcholinesterase (AChE) while plasma contains a less specific cholinesterase (ChE). We reported at a previous meeting [Blood 2008, 112(11) Abst #3849] that AChE activity of RBC-derived microparticles (RMP) is 6 times higher than those in PMP. In this study we measured plasma ACTH levels in several groups and encountered unexpectedly high plasma ChE activities in patients with TIA and other thrombosis.

Methods.

(i) Patient population.
A series of n=108 consenting patients were recruited sequentially having various disorders For purpose of analysis, they were divided in 2 main groups: n=53 with thrombosis (TBS), F/M 27/26; and n=55 non-TBS, F/M 24/31. Thrombosis group consists of venous and arterial thrombosis including those with TIA. Non TBS group consists of anemias, thrombocytopenias including ITP, MDS.

(ii) Assay
was essentially by Ellman's method. In our system, milli-absorbance units/min (mA/min) x 0.065 = umols substrate cleaved/min. Values reported here are in unitsof mA/min per mL plasma. Normal controls (NC, n=14) had a cutoff of 3000 mA/min per mL plasma, = mean +2SD.

(iii) Sample handling.
Platelet-poor plasma (PPP) was prepared by centrifuging 10 min at 1800 xg, then frozen in aliquots. For assay, it was diluted 1:20 with saline, then 5 uL and 10 uL were used in 96-well microtiter plate.

Results:
(i) Significantly higher ChE activity was observed in thrombosis (TBS) patients compared to non-TBS. Mean value ±SD in TBS was 2928 ±773, and in Non-TBS was 1897 ±713 (units as above). This difference was significant, p<0.001. (ii) When analyzed elevated levels of ACTH above 2SD of normal controls (n=26) between 2 groups, the TBS group had elevated ChE (>3000) in 30% of patients, while the Non-TBS had elevated ChE in 7.8%. (iii) Further analysis among thrombosis group revealed that the subgroup with neurological TBS (TIA, minor strokes) had the most consistent elevations of ACTH; 10 of15 with TIA group (66%) had ChE activities >3000.

Summary/ Discussion.
Although ChE and AChE in blood has long been studied, to our knowledge, this is the first report to show a relation between plasma ChE and thrombosis. Its elevation is very pronounce in thrombosis of the CNS, manifesting as TIA. Further study is warranted to elucidate how ChE is related to AChE of the CNS and on red cells.

Disclosures:
No relevant conflicts of interest to declare.
Pharmacokinetics of Intravenous Uricase-PEG 20, a Drug for Managing Hyperuricemia in Tumor Lysis Syndrome.
Authors: Zhang Zhihua , Fiorino Anthony 
Published: October 2019

Abstract
Abstract 3086
Poster Board III-23

Background
Tumor lysis syndrome can result in hyperuricemia and the precipitation of monosodium urate crystals in the renal tubules, leading to renal failure and dialysis. The enzyme uricase, found in most mammals but not humans, metabolizes uric acid into the highly soluble allantoin. Rasburicase (Elitek/Fasturtec, Sanofi Aventis), an unmodified recombinant uricase, is used to treat and prevent hyperuricemia associated with tumor lysis syndrome. However, it requires multiple doses and is highly immunogenic. Uricase-PEG 20 is a pegylated recombinant uricase, designed to have an extended half life and reduced immunogenicity compared with unmodified uricase, that has been administered intramuscularly to gout patients in clinical studies. However, it has not previously been studied as an intravenous agent.

Methods
Intravenous toxicology studies, including pharmacokinetic studies, were performed with Uricase-PEG 20 in rats and cynomolgus monkeys. Uricase-PEG 20 was administered to rats at 1, 4 and 10 mg/kg and uricase enzyme activity was assessed at 1, 6, 24, 72 and 144 hrs after dosing. In monkeys, Uricase-PEG 20 was administered at 0.5, 1 and 5 mg/kg and uricase activity was assessed at 15 min and 1, 4, 24, 72 and 144 hrs after administration.

Results
In rats, the half-life for Uricase-PEG 20 ranged from 44.2 to 104.5 hrs (median, 70.7 hrs); the volume of distribution varied from 38.8 to 129.0 mL/kg (median 94.6), and the clearance varied from 0.70 to 1.48 mL/hr/kg. In monkeys, the half-life ranged from 184 to 214 hrs (median 194.5 hrs), the volume of distribution ranged from 17.2 to 25.2 mL/kg (median 19.9 mL/kg), and the clearance ranged from 0.063 to 0.102 mL/hr/kg. In both species, measures of exposure including Cmax and AUClast increased in a dose-proportional manner. The median half-lives of 70.7 hrs in rats and 194.5 hrs in cynomolgus monkeys is significantly longer than the half-life reported for rasburicase in similar models (<2 hrs in rats and <4 hrs in baboon monkeys).

Conclusions
The long half-life of Uricase-PEG 20 compared to that of unmodified uricase suggests that Uricase-PEG 20 may require less frequent dosing and thus have better clinical utility than unmodified uricase. Uricase-PEG20 will be used at intravenous doses ranging from 0.05 to 0.4 mg/kg in initial human studies.

Disclosures
Zhang: EnzymeRx: Employment. Fiorino:EnzymeRx: Employment.
Sall4, a Stem Cell Factor, Promotes Chemoresistance by Regulates the Side Population Cell Phenotype.
Authors: Jeong Ha-Won , Cui Wei , Guo Ye , Yang Youyang , Lu Jiayun , Gao Chong , Chai Li 
Published: October 2019

Abstract
Abstract 3093
Poster Board III-30
The side population (SP) phenotype, defined as the verapamil-blockable ability to efflux the nucleic acid dye Hoechst 33342, has been used to enrich for stem cells in several human normal tissues, cancers, and multiple cell lines including blood cells, and thus may be useful for the identification and isolation of cancer stem cells, which has emerged as a new therapeutic target for cancer treatment. However, the molecular mechanism(s) operating in SP cells remain unclear. Previous studies show that the stem cell factor, SALL4 plays a central role in the self-renewal of embryonic and leukemic stem cells. In this study, we determined the role of SALL4 in side population (SP). Using FACS sorting, we found the presence of SP fractions in four leukemic cell lines: HL-60, NB-4, RPMI8226 and KG1a. SALL4 expression was more abundant in SP cells compared with non-SP cells by 2- 4 fold in these leukemic cell lines. Knockdown of SALL4 in purified SP cells resulted in a reduction of SP population, indicating that SALL4 is required for the self-renewal of SP cells in this culture system. Since the side population phenotype is known to be mediated by the ATP-binding cassette proteins, we further investigated whether SALL4 could regulate the ATP transporters in SP cells. Chromatin immunoprecipitation (ChIP), luciferase assays and real-time PCR analysis demonstrated that SALL4 could bind to the promoter region of ABCA3, one of the ABC transporters, and activated its expression. In addition, while overexpression of SALL4 led to drug resistance in cell lines, SALL4-knockdown cells displayed more sensitive to drug treatments than the control cells. Further more, SALL4 expression was associated with primary AML treatment status (N= 64 cases), with higher SALL4 mRNA expression seen in drug resistance and partial remission patients than that from complete remission cases. Taken together, our results suggest that SALL4 plays an important in the sensitivity to drug treatment, at least in part, through the maintenance of SP cells, and is responsible for drug-resistance in leukemia.

Disclosures
No relevant conflicts of interest to declare.
Comorbidity Is An Independent Prognostic Factor in AML: Comparison of Two Comorbidity Scores.
Authors: Novotny Juergen , Aisenbrey Achim , Nückel Holger , Dührsen Ulrich 
Published: October 2019

Abstract
Abstract 3106
Poster Board III-43

Objective
Many factors have been studied to predict outcome and allocate treatment in AML. The best established prognostic factors are karyotype and age. However, comorbidity may play an important role in the outcome of AML. We applied two comorbidity scores at the time of first admission in order to test this hypothesis.

Methods
We retrospectively analysed 198 consecutive patients with AML. All patients were included irrespective of the applied therapy. Karyotype risk group was 11.6 % good, 68.0 intermediate and 20.4 % poor risk, respectively. The median survival was 382 days. The median age was 62 years (range 20 – 81), 95 were male, 103 were female. The criteria of the Charlson Comorbidity Index (CCI) and the recently developed Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) were applied. However, the cut-offs were set lower than in the original publication in order to detect the possible impact of minor comorbidity.

Results
In our study, the HCT-CI (left figure) separated clearly between patients with a score of more than one (dotted line), one (dashed line) and zero (continous line) (median survival: 100 vs 328 vs 718 days; log rank test p<0.0001). Similarly, the CCI separated the patients with more than one (dotted line), one (dashed line) and none (continous line) (median survival: 94 vs 293 vs 515 days; log rank test p<0.0001). Karyotype (p < 0.001), HCT-CI (p = 0.003) and age (cut-off 60 years; p = 0.006) we shown as independent risk factors by multivariate analysis. The CCI (right figure) separated only between patients with a score of zero (continous line) and those with at least one score point. Patients with one (dashed line) and patients more than one (dotted line) were not separated.

Conclusions
Our findings show that HCT-CI is an additional prognostic factor in AML, at least in our cohort. We extend previous findings severalfold. Firstly, our analysis includes 90 patients younger than 60 years and was not restricted to patients older than 60 years.
Secondly, we directly compared two comorbidity indices, showing that the HCT-CI discriminaates between three risk groups. Thirdly, we showed that comorbidity is an independent predictor for survival.
In conclusion comorbidity seems to be an independent prognostic factor and should be studied prospectively to clarify its use for stratification in therapeutic studies.

Disclosures
No relevant conflicts of interest to declare.