bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resource Use and Expenditures Among Adult Sickle Cell Patients with and without Depression
Authors: Kamble Shital , Reed Shelby D , Flahiff Charlene , Adam Soheir , DeCastro Laura M 
Published: October 2019

Abstract
Abstract 1534

Objective:
Depression is commonly associated with less favorable medical outcomes among patients with sickle cell disease (SCD), yet little is known about its associated impact on medical resource use and expenditures. In this study, we descriptively compared inpatient stays, number of hospital admissions, emergency department (ED) visits, outpatient visits, and expenditures for SCD patients with and without depression.

Methods:
150 adult SCD patients were prospectively enrolled in a cross-sectional cohort study in 2009 to evaluate the prevalence of depression and its association with quality of life, disease severity scores measuring end organ damage, and health care utilization. Detailed cost accounting and administrative physician billing records from the Duke University Health System were obtained for all enrolled patients and used to generate estimates of medical care utilization and costs. Indexing on the enrollment date, we included data representing one year prior to and six months following study entry. Based on the Beck Depression Inventory (BDI) scores, we categorized SCD patients into those with depression (BDI score ≥14) and those without depression (BDI score <14). Given the skewed distributions of resource use and expenditures, we used generalized linear regression models (GLM) with negative binomial distributions and log links to compare inpatient stays, number of hospital admissions, ED visits, and outpatient visits and GLMs with gamma distributions and log links to compare costs associated with each resource use category between patients with and without depression.

Results:
Data from 142 patients analyzed, 81 females and 61 males with a mean age of 34.2 years. We identified 50 patients with depression and 92 patients without depression. At study entry, females represented 72% of SCD patients with depression and 49% of SCD patients without depression (P< 0.01). Median age was 32.5 years among patients with depression and 29.5 years among those without depression (P= 0.22). Hospital admissions, ED visits, and outpatient visits were generally similar between patients with and without depression one year prior to and six months after study entry. Patients with depression spent more days in the hospital during both time periods. Total inpatient expenditures, including physician fees paid, were higher for patients with depression than those without depression for both time periods (Table).

Conclusion:
SCD patients with depression incur higher expenditures and longer stays than SCD patients without depression. Efforts should be made for early diagnosis and active therapeutic intervention for depression among SCD patients, to decrease health care utilization and cost.

Disclosures:
No relevant conflicts of interest to declare.
GSK3β Signaling Regulates the Motility of Hematopoietic Progenitors Via Prune.
Authors: Lapid Kfir , D‘Uva Gabriele , Kalinkovich Alexander , Ludin Aya , Golan Karin , Itkin Tomer , Zollo Massimo , Lapidot Tsvee 
Published: October 2019

Abstract
Abstract 1553
One of the hallmarks of hematopoietic stem and progenitor cells (HSPC) is their motility. In steady state, HSPC are mostly retained in the bone marrow (BM), allowing ongoing hematopoiesis, concomitantly with slow release to the circulation as part of homeostasis and host defense mechanisms. While stress-induced recruitment and clinical mobilization processes are extensively studied, steady state egress mechanisms are poorly understood. In this study, we demonstrate that inhibition of Glycogen Synthase Kinase 3b (GSK3β) directly or via upstream Insulin-like Growth Factor-1 (IGF-1) signaling limited murine HSPC egress to the circulation. Indeed, inhibition of GSK3β resulted in reduced HSPC migration capacity towards a gradient of the chemokine stromal derived factor-1 (SDF-1, also termed CXCL12) in vitro and was found to reduce HSPC mobilization by IGF-1 receptor antagonist treatment. Interestingly, GSK3β signaling also regulated SDF-1 transcription by BM stromal cells in vitro and in vivo, probably as part of HSPC maintenance, since murine CXCR4 signaling is essential for hematopoietic stem cell quiescence. We revealed that the involvement of GSK3β in directional HSPC motility is mediated by the downstream phosphodiesterase Prune. Prune, which is over-expressed in several human cancers, was recently found to localize in focal adhesion sites, promoting the motility of malignant cells. Herein, we show that Prune is also expressed in normal leukocytes, including HSPC. Accordingly, inhibition of Prune resulted in reduced SDF-1 induced migration of murine HSPC in vitro as well as reduced steady state egress in vivo. Prune activity was also shown to regulate the actin cytoskeleton by contributing to its polymerization. In general, highly regulated actin turnover is essential for spontaneous and directional motility mechanisms. Altogether, we present GSK3β and Prune as novel players in physiological HSPC motility, dictating an active rather than passive nature for steady state egress from the BM reservoir to the blood circulation as part of homeostasis.

Disclosures:
No relevant conflicts of interest to declare.
Synergy Between Kit Ligand (KL) and IL-4 In Mast Cells Is Mediated by Cross-Receptor Interactions In Lipid Rafts.
Authors: Mani Maheswaran , Venkatasubrahmanyam Shivkumar , Yang Yujun , Krampf Mark , Huang Jing , Butte Atul , Jahn Thomas , Weinberg Kenneth I. 
Published: October 2019

Abstract
Abstract 1564
Studies of erythroid and thymic differentiation have shown that cross-receptor interactions between the stem cell factor receptor Kit, a receptor tyrosine kinase (RTK), and tissue-restricted Type I cytokine receptors (EpoR and IL-7R, respectively) are necessary for normal development of each lineage. To determine whether these Kit-Type I cytokine receptor interactions are a ubiquitous phenomena in Kit (+) hematopoietic cells, we studied murine bone marrow derived mast cells (BMMC), which express Kit and IL-4R, and are responsive to both cognate ligands. Both KL and IL-4 were individually mitogenic; combinations of KL and IL-4 synergistically promoted BMMC proliferation, even at suboptimal concentrations of each ligand (Synergy Index 2.7 for SCF 20ng/ml + IL-4 5ng/ml). Similar to the results seen previously with Kit and EpoR or IL-7R, activation of Kit by KL resulted in cross-receptor tyrosine phosphorylation of the IL-4Rα and γc subunits of IL-4R, even in the absence of their cognate ligand, IL-4. Each subunit of the IL-4R was independently phosphorylated by activated Kit, in the absence of Jak3. Furthermore, in the malignant mast cell line HMC-1, inhibition of oncogenic Kit by imatinib also reversed constitutive phosphorylation of IL-4R. Previous studies have shown that STAT 1α, STAT 5A, and STAT 5B, but not Stat6, are bound to and directly phosphorylated by activated Kit. In contrast, STAT6 is activated by engagement of IL-4R by its cognate ligand. Cross-receptor phosphorylation of IL-4R by activated Kit in BMMC induced STAT6 phosphorylation, with the same apparent pI as after activation of IL-4R by cognate ligand. Subcellular fractionation showed that activated Kit, γc, Jak3, and STATs were localized in lipid raft fractions upon KL stimulation. Inhibition of lipid raft formation by MβCD resulted in loss of both cross-receptor tyrosine phosphorylation of IL-4R by Kit and synergistic proliferation, but not proliferation induced by each cognate ligand. Gene expression analyses of KL stimulated BMMC from wt and IL-4Rα/γc deficient mice demonstrated that over 30% of the Kit gene signature was dependent on the presence of the IL-4R. Together, the data indicate that the synergy of KL and IL-4 in BMMC is mediated by cross-receptor interactions between Kit and IL-4R in raft membrane microdomains. The Kit-IL-4R interaction is the third cross-receptor interaction described between the Kit RTK and a tissue-restricted Type I cytokine receptor. Besides RBC, thymocytes, and mast cells, such cross-receptor interactions are likely to be a general mechanism for synergistic and tissue-specific pleiotropic signaling by Kit in hematopoiesis and possibly other cell types, e.g., various Kit (+) stem cell populations and cancers.

Disclosures:
No relevant conflicts of interest to declare.
Treatment with mTOR Inhibitor, Everolimus (RAD001) Overcomes Resistance to Imatinib In Ph-Leukemia Quiescent Cells.
Authors: Kuwatsuka Yachiyo , Minami Yosuke , Minami Miho , Tanizaki Ryohei , Kiyoi Hitoshi , Naoe Tomoki 
Published: October 2019

Abstract
Abstract 1579
Recent studies suggest that leukemia stem cells (LSCs) are responsible for relapse of leukemia and eradication of LSCs should be necessary for the cure. In order to examine mechanisms of drug resistance in Ph+ leukemia to imatinib (IM) due to stem cell properties and to seek strategies to overcome the resistance, we've previously established in vivo-murine and ex vivo-culture models using murine hematopoietic pluripotent progenitors transduced with BCR-ABL (Minami, et al., PNAS, 2008). Furthermore, Ph+ leukemia (including T315I-, F311I-mutated CML-BC, or Y253H-mutated Ph-ALL) patient cells were serially xenotransplanted into immunodeficient NOD/SCID/IL2rγnull (NOG) mice. Engrafted bone marrow and spleen cells were almost identical to the original leukemia cells as to phenotypes including karyotypes and distribution of primitive populations. Spleen cells from leukemic NOG mice were treated ex vivo with IM and growth factors, and cell viablility (PI/AnnexinV-staining) was compared between treated and non-treated cells. After treatment with IM, significantly more residual cells were observed in the CD34+/38- population compared to the CD34+/38+ or CD34-/38+ populations. Phosphorylation of BCR-ABL and CrkL was completely inhibited in all populations with IM treatment. Regarding cell cycle states, a higher percentage of quiescent slow-cycling (Hoechst 33342low/Pyronin Ylow) cells was observed in the CD34+/38- population relative to the other populations. Recently, aberrant activation of mTOR signaling has also been reported to be involved in LSCs. Leukemic spleen cells in longer co-culturing with stromal cells were treated with IM and mTOR inhibitor, everolimus (Eve, RAD001). While slow-cycling CD34high+ cells were insensitive to IM, combination treatment with IM and Eve induced significant cell death also in the quiescent population. In vivo-treatment with Eve decreased tumor cells in leukemic NOD mice inoculated with the leukemic NOG cells under the sub-lethally irradiated condition. Treatment with Eve also reduced long-term colony formation of Ph+ leukemia patient samples including Y253H-mutated Ph-ALL with less toxicity to normal cord blood cells. These results imply that treatment with Eve is promising for overcoming the resistance to IM due to quiescent property in Ph+ LSCs.

Disclosures:
Naoe: Kyowa-Kirin: Research Funding; Novartis: Research Funding; Janssen: Research Funding.
Inhibition of Plasminogen Activator Inhibitor (PAI)-1 Corrects Diabetic CD34+ Dysfunction.
Authors: Hazra Sugata , Jarajapu Yagna P.R. , Liu Li , Caballero Sergio , Stepps Valerie , Bhatwadekar Ashay , Boulton Michael E. , Higgins Paul J. , Bartelmez Stephen H. , Grant Maria B. 
Published: October 2019

Abstract
Abstract 1601

Objective:
The dysfunction of human diabetic CD34+ endothelial progenitor cells limits their utility in autologous cell therapy for vascular complications. Previously, we showed that transient inhibition of transforming growth factor-beta 1 (TGF-β1) enhances vascular reparative function of human CD34+ cells isolated from diabetics (Bhatwadekar et al, 2010). Expression of PAI-1, the major gene product of TGF-β1 activation, is increased by high glucose and insulin exposure in endothelial cells and PAI-1 has been shown to be increased in the serum of diabetics. We asked whether the beneficial effects of TGF-β1 blockade on CD34+ cells function were mediated by inhibition of PAI-1 and whether blocking of PAI-1 could correct diabetes associated dysfunction of these cells.

Research Design and Methods:
Plasma determinations of PAI-1 and TGF-β1 (both measured by ELISA) were compared in type 2 (n=17) and type 1 (n=7) diabetic patients. CD34+ cells from these individuals were isolated and analyzed for cell survival (in the presence and absence of growth factors), cell proliferation, cell cycle analysis and migration. The effect of TGF-β1 phosphorodiamidate morpholino oligomers (PMO) treatment on PAI-1 level was determined in CD34+ cells. In CD34+ cells, PAI-1 was blocked using either lentivirus expressing PAI-1 shRNA or PAI-1 siRNA. In vivo homing ability of PAI-1 inhibited CD34+ cells was assessed using an ocular model of ischemia/reperfusion (I/R) Injury.

Results:
Plasma PAI-1 level was increased in type 2 diabetic patients compared to type 1 (p<0.05) and directly correlated with TGF-β1 plasma levels (r= 0.44). TGF-β1 PMO treatment resulted in a reduction of PAI-1 mRNA expression (p=0.0018 in diabetic, p=0.05 in non-diabetic). PAI-1 blockade promoted EPC proliferation in vitro and bypassed the inhibitory effect of TGF-β1 on cell survival (p<0.001) even in the absence of growth factors. PAI-1 blockade enhanced the migration of these cells in response to SDF-1α in (p<0.01) compared to cells treated with scrambled siRNA and improved the in vivo re-endothelialization by CD34+ cells in the I/R model.

Conclusions:
Our results suggest that the cytostatic activity of TGF-β1 in CD34+ cells is mediated largely through PAI-1. Blocking PAI-1 corrects multiple defects in CD34+ cells from type 2 diabetic patients. This approach may offer a promising therapeutic strategy for restoring vascular reparative function in diabetic cells and facilitate their use in autologous cell therapy.

Disclosures:
No relevant conflicts of interest to declare.
CBL Mutations In Pediatric Acute Myelogenous Leukemia Are a Rare Event, a Report From the Children's Oncology Group.
Authors: Kutny Matthew A. , Miller Kristen , Alonzo Todd A. , Gerbing Robert B. , Ho Phoenix A. , Gamis Alan S. , Raimondi Susana C. , Hirsch Betsy A. , Meshinchi Soheil 
Published: October 2019

Abstract
Abstract 1659

The CBL gene encodes a ubiquitin ligase that targets multiple activated tyrosine kinases for degradation. Analysis of several series of patients with myeloid malignancies demonstrated mutations in the RING finger domain and linker domains encoded by exons 8 and 9 of the CBL gene. Loh, et al (Blood, 114:1859-63, 2009) analyzed 159 samples from pediatric patients with juvenile myelomonocytic leukemia (JMML) for mutations in those exons. They found CBL mutations in 27 (17%) of the samples. We sought to determine the prevalence of mutations in CBL exons 8 and 9 in pediatric patients with de novo acute myeloid leukemia (AML). We analyzed 290 samples from pediatric patients treated on the Children's Oncology Group study AAML03P1. DNA was isolated from diagnostic bone marrow samples. Exons 8 and 9 of the CBL gene were amplified by PCR and then sequenced for mutational analysis. Five of 290 (1.7%) patients had CBL exon 8 or 9 mutations (Table 1). Patient 1 had a heterozygous splice site mutation (1096 –1G>T). Patient 2 had a homozygous missense mutation (C384S). Splice-site mutations and mutations of the C384 residue were also seen in JMML. Two patients had synonymous heterozygous mutations (P433P and I429I), and 3 patients had heterozygous insertions and deletions. Patient 3 had a 121-bp deletion that included 66 base pairs at the 3’ end of exon 8 and the first 55 base pairs of intron 8. Loh, et al (Blood, 2009) also found a similar 99-bp deletion in JMML. Patient 4 had a 3-bp duplication in exon 9 (1382-1383ins TGA) with TGA repeated 7 times; TGA is repeated 6 times in wild-type cells. Patient 5 had a complex insertion and deletion: 73 base pairs (31 base pairs in intron 7 and 42 base pairs at the 5’ end of exon 8) were deleted, and 26 base pairs were inserted at the site of the deletion. We examined the clinical features and other genetic abnormalities among these 5 patients with CBL mutations. All of the patients had an abnormal karyotype, including monosomy 7, t(8;21), t(9;11), or inv(16). We tested FLT3 status (internal tandem duplications and point mutations), CEBPA, and NPM1. Patient 5 had a FLT3 point mutation. We conclude that CBL mutations in the RING finger and linker domains are rare in pediatric de novo AML compared to their prevalence in JMML.

Disclosures:
No relevant conflicts of interest to declare.
Activation of a Novel Palmitoyltransferase through a t(6;14) Translocation In T/Myeloid Biphenotypic Leukemia and Subsets of Acute Myeloid Leukemia.
Authors: Ning Yi , Yu Lei , Reader Jocelyn , Chen Ching , Zhao Xianfeng Frank , Ha Jung Sook , Lee Charles , York Teresa , Gojo Ivana , Baer Maria R 
Published: October 2019

Abstract
Abstract 1663
The current World Health Organization (WHO) classification of hematologic malignancies includes a number of entities defined by specific genetic abnormalities. Most known abnormalities result from chromosomal translocations and mutations involving genes encoding transcription factors or tyrosine kinases. We identified the activation of a novel palmitoyltransferase, ZDHHC14, through a chromosomal translocation, t(6;14)(q25;q32). This translocation was initially documented by three independent groups in two children and two adult patients with T/myeloid biphenotypic leukemia, a poorly differentiated form of acute leukemia with a single population of leukemic blasts co-expressing antigens of both T-lymphoid and myeloid lineages. Recently, we detected the same translocation in two additional patients with T/myeloid biphenotypic leukemia. Molecular characterization of the translocation breakpoints revealed the juxtaposition of a regulatory region downstream of BCL11B (at chromosome region 14q32) upstream of an uncharacterized gene, ZDHHC14 (at chromosome region 6q25), leading to transcriptional activation of the ZDHHC14. Notably, this regulatory region from 14q32 has been found to be responsible for transcriptional activation of a homeobox gene, TLX3, as a result of a cryptic translocation t(5;14)(q35;q32) in T-cell acute lymphoblastic leukemia. Our subsequent survey of ZDHHC14 protein levels in blasts from patients with various subtypes of acute myeloid leukemia (AML) showed that the protein was not detectable in AML patients with t(8;21), t(15;17), or inv(16), but was detected in AML patients with FLT3 mutations or with complex karyotypes, indicating a possible association of increased expression of this protein with unfavorable prognostic features of the disease. We also demonstrated that overexpression of ZDHHC14 could inhibit TPA-induced cellular differentiation of K562 cells. Interestingly, the Drosophila homolog of ZDHHC14 has been found to be a palmitoyltransferase regulating Fat signaling. Fat is a Drosophila tumor suppressor gene, encoding a large cadherin that regulates growth and a form of tissue organization. While the function of ZDHHC14 and the role of protein palmitoylation in mammalian hematopoiesis remain unknown, recent studies in neuronal development have demonstrated that palmitoylation regulates diverse aspects of protein trafficking. Our findings suggest that palmitoyltransferase plays a previously unappreciated role in hematopoiesis and that increased expression of ZDHHC14 may be associated with a primitive status of leukocytes. Further characterization of ZDHHC14 may broaden our knowledge of leukemogenesis, contribute to risk stratification of acute leukemia, and provide a novel therapeutic target.

Disclosures:
No relevant conflicts of interest to declare.
Oxidant Pathway Functional Polymorphisms Influence the Risk of Myeloid Leukemia/Transient Myeloproliferative Disorder In Children with Down Syndrome.
Authors: Pope Jennifer M. , Kim Mi-Ok , Alonzo Todd A. , Gerbing Robert B. , Rayburg Melissa , Radloff Gretchen , Gamis Alan S. , Davies Stella M. , Perentesis John 
Published: October 2019

Abstract
Abstract 1680
Individuals with Down syndrome have a 2% cumulative risk for the development of leukemia by the time they reach 30 years of age. In addition, as many as 5–10% of infants with Down syndrome may develop a transient myeloproliferative disorder (TMD). The molecular basis for the increased risk for hematologic disorders and other congenital developmental abnormalities with DS remains unknown. Additional genetic material from the critical Down syndrome locus at 21q22 includes the Cu/Zn superoxide dismutase gene and other genes contributing to high oxidative stress and increased endogenous DNA damage observed in cells from patients with Down syndrome. We hypothesized that functional polymorphic variants in enzymes associated with detoxification of oxidants and repair of oxidant associated DNA damage would be associated with an increased risk for the development of myeloid leukemia (ML) and TMD in children with Down syndrome. We studied the role of functional polymorphisms in the oxidant metabolizing genes, Paraoxonase 1 (PON1) and NADH/NADPH oxidase p22 phox (P22_PHOX) in the potential genetic etiology of ML/TMD in children with Down syndrome. Genotyping was conducted in 192 patients with Down Syndrome ML or TMD, and 251 healthy blood donor controls. All genotype frequencies in patients and control populations were consistent with those expected from Hardy-Weinberg equilibrium. We found that the variant PON1 Gln192Arg allele, associated with reduced free radical metabolism, occurred at a higher frequency in the Down syndrome ML/TMD population compared to healthy controls (OR, 2.71; 95% CI, 1.50–4.97; p=0.0003). Consistent with our hypothesis of increased oxidant sensitivity in these patients, we also observed decreased frequency of the protective variant P22_PHOX His72Tyr allele, purportedly associated with reduced generation of reactive oxygen species, in the Down syndrome ML/TMD population compared to healthy controls (OR, 0.48; 95% CI, 0.23–0.95; p=0.025). Notably, the variant PON1 Gln192Arg allele has also been associated with increased risk for non-Hodgkin's lymphoma in adults (Kerridge et al. Br J Haematol, 2002). Conclusion: These preliminary studies suggest that functional polymorphic variants in the oxidant metabolizing enzymes PON1 and P22_PHOX may influence risk for development of ML/TMD in children with Down syndrome. Studies to confirm these observations in a separate cohort of patients are in progress.

Disclosures:
No relevant conflicts of interest to declare.