bluuebunny/crossref_metadata_2025_split huggingface dataset:
STAT5-Induced Self-Renewal and Impaired Myelopoiesis of Human Hematopoietic Stem/Progenitor Cells Involves Downmodulation of C/EBPα.
Authors: Schuringa Jan Jacob , Wierenga Bart-Jan , Schepers Hein , Moore Malcolm A.S. , Vellenga Edo 
Published: April 2020

Abstract
Previously, we demonstrated that enforced activation of STAT5 in human cord blood (CB)-derived stem/progenitor cells results in enhanced long-term stem cell self-renewal and impaired myelopoiesis (J.J.Schuringa et al, J.Exp.Med. 2004;200:623). Now, C/EBPα was identified as a critical transcription factor that is downregulated by STAT5. Affymetrix microarray analysis on STAT5A(1*6)-transduced CD34+ cells identified C/EBPα as the most prominently downregulated gene (−3.3 fold), and these data were confirmed by RT-PCR and Western blotting. To determine the cell-biological relevance of these observations, a 4-OHT-inducible C/EBPα-ER protein was co-expressed with the STAT5A(1*6) mutant in CB CD34+ cells by using a retroviral approach. Re-expression of C/EBPα in STAT5A(1*6) cells resulted in a marked restoration of myelopoiesis as determined by morphological analyses, FACS analyses for myeloid markers such as CD11b, CD14 and CD15, and RT-PCR for myeloid-restricted genes such as g-csfr. While enforced activation of STAT5A resulted in accelerated erythropoiesis, this was blocked when C/EBPα was re-introduced into STAT5A(1*6) cells. Similarly, the proliferative advantage imposed on CD34+ cells by STAT5A(1*6) depended on the downmodulation of C/EBP as reintroduction of C/EBPα in these cells induced a quick cell cycle arrest and the onset of myeloid differentiation. At the stem/progenitor cell level, LTC-IC frequencies were elevated from 0.5% to 11% by STAT5A(1*6) as compared to controls, but these elevated LTC-IC frequencies were strongly reduced when C/EBPα was reintroduced in STAT5A(1*6) cells. Enumeration of progenitors in methylcellulose assays revealed similar results, the number of CFCs was reduced over 10-fold when C/EBPα was expressed in STAT5A(1*6) cells. Also, secondary CAFCs and long-term cultures could only be generated from STAT5A(1*6) expressing cells, but not from cells that co-expressed STAT5A(1*6) and C/EBPα. Taken together, these data indicate that STAT5-induced self-renewal and impaired myelopoiesis involves downmodulation of C/EBPα.
Hepcidin Expression Is Correlated with Erythropoietic Indexes and Non-Transferrin-Bound Iron Levels in Patients with Thalassemia Major.
Authors: Kattamis Antonios , Papassotiriou Ioannis , Palaiologou Danai , Drakaki Kalliopi , Apostolopoulou Filia , Papanikolaou George 
Published: April 2020

Abstract
Hepcidin plays a central role in iron homeostasis. Hepcidin seems to be the common final mediator of both erythroid and stores regulators, and coordinates intestinal iron absorption and iron release from reticuloendothelial macrophages. The erythroid regulator probably dominates over the stores regulator. Iron overload in thalassemia major is attributed mainly to blood transfusions and partly to increased iron absorption. Urine hepcidin levels in regularly-transfused thalassemia patients are inappropriately low in regards to their iron stores. Liver hepcidin expression is suppressed in the murine model of human thalassemia (Hbbth3/+). We evaluated the correlation between indexes of iron stores and of erythropoiesis and liver hepcidin expression in patients with thalassemia major. Nineteen transfusion-dependent thalassemic patients (14 females) of 20±7.2 years of age underwent liver biopsy. Fourteen patients were seronegative for hepatitis C. Liver iron concentration (LIC) was estimated by atomic absorption spectrometry. Hepcidin mRNA expression levels were estimated by quantitative Real-Time PCR (Lightcycler, Roche) from isolated RNA from liver tissue. Hematologic and blood chemistry parameters were determined by standard methods. NTBI was measured in 13 patients by atomic absorption spectrometry. Statistical analysis was performed using non-parametric tests. Hepcidin expression ranged from 0.08 to 38.4 (median 1.13) arbitrary units. The most significant correlations between hepcidin and indexes of erythropoesis and of iron load are shown on the table.
Variable median (range) hepcidin LIC NTBI r = Spearman’s rho, n.s. = non statistical Ferritin (μg/L) 2174 (990–5963) n.s. n.s. n.s. Hb (g/dL) 12 (11.2 – 13.4) r:0.55, P:.017 r:-0.43, P:.071 n.s. sTfR (mg/L) 2.64 (0.75 – 5.75) r:-0.59, P:.01 r:0.51, P:.03 r:0.71, P:.006 EPO (IU/L) 21.6 (2.9 – 106) r:-0.61, P:.007 r:0.56, P:.015 r:0.63, P:.02 NTBI (μmol/L) 3.1 (0.9 – 4.5) r:0.56, P:.047 r:0.67, P:.012 LIC (μg Fe/d.w.tissue) 8.3 (3.1 – 18.9) n.s.
The correlations between hepcidin and Hb, sTfR, EPO were stronger when patients with infectious hepatitis were excluded from analysis. Hepcidin did not correlate with any indexes of iron load, including LIC, ferritin, serum iron, transferrin saturation and annual transfusional iron load. Our results provide additional evidence that increased erythropoietic activity down-regulates hepcidin expression. The lack of correlation between iron stores and hepcidin expression is in consistency with the hypothesis that increased erythropoietic activity dominates over iron stores in the regulation of hepcidin expression in patients with thalassemia major. Furthermore, the negative correlation between NTBI and hepcidin RNA levels underlies the role of hepcidin in iron body trafficking even in hemosiderotic patients.
Altered Expression of Transcription and Chromatin Remodeling Factors in Deletional HPFH.
Authors: Costa Fernando F. , de Andrade Tiago G. , Cunha Anderson F. , Fattori André , Saad Sara T.O. 
Published: April 2020

Abstract
Hereditary Persistence of Fetal Hemoglobin is a rare, heterogeneous and benign group of hereditary disorders with an abnormal switch from fetal to adult hemoglobin, resulting in high levels of Hb F in the adult stage. A total of six deletions related to HPFH have been described, associated with increased levels of both gamma chains. Three main hypotheses have been proposed to explain the relationship between these deletions and the non-suppression of gamma genes: the removal of competitive regions that interact with the LCR; the juxtaposition of enhancer elements; and the removal of silencers. Despite evidence to support these hypotheses, however, they are not conclusive. Recently, Xiang and cols (Abstract #1215, 2004 ASH Meeting; Blood, Volume 104, issue 11, November 16, 2004) developed a YAC construct with the whole beta-globin locus containing a deletion of approximately 83.5 Kb responsible for the HPFH-2. Unexpectedly, the gamma gene was completely silenced in the adult transgenic mice. These data suggest that other mechanisms could be involved in the increased levels of HbF in these conditions. The authors speculate that other regions upstream from the cluster may harbor this activity. We, herein, investigate the possible involvement of transcription factors, using the subtractive hybridization method to identify differentially expressed transcripts in reticulocytes from a normal subject and a HPFH-2 subject. We have identified 56 and 106 unique genes in the normal and HPFH-2 cDNA libraries, respectively. Some of these are transcription (zinc fingers and homeobox proteins) and chromatin remodeling (NAP and SWI like proteins) factors that could participate in globin gene regulation. These genes are located in cis or in trans to the deletion and their altered gene expression has been confirmed by Quantitative Real-time PCR in other two HPFH subjects. The data may present new clues about globin gene regulation, the increased expression of gamma gene in deletional HPFH and the dynamic organization of genes and chromosomes in cells.
High Prevalence of Fractures and Bone Pain in Thalassemia: The Thalassemia Clinical Research Network Experience.
Authors: Vogiatzi Maria , Macklin Eric , Schneider Robert , Lane Joseph , Olivieri Nancy , Kirby Melanie , Cheung Angela , Vichinsky Elliott , Fung Ellen , Cohen Alan , Kwiatkowski Janet , Stallings Virginia , Holm Ingrid , Neufeld Ellis , Giardina Patricia J. 
Published: April 2020

Abstract
Historically fractures and bone pain have been frequent problems in Thalassemia. Recently a cross-sectional observational study conducted by the North American Thalassemia Clinical Research Network (TCRN) found a high prevalence of low bone mass among the various Thalassemia syndromes. In addition, the prevalence of fractures and bone pain with contributing factors were determined and reported below. The study population consisted of 369 patients: 65% had Thalassemia Major (TM), 12% Thalassemia Intermedia (TI), 12% Beta E (βE), 5% hemoglobin H (HbH), 5% hemoglobin H/Constant Spring (HbH/CS) and 1% Homozygous alpha (Hα). A 35% prevalence of fractures which increased with age was identified (6–10 yrs: 1.1/100 pt-yrs; 11–19 yrs: 1.2/100 pt-yrs; 20+ yrs: 2.1/100 pt-yrs). Fractures occurred more frequently in males vs. females (40% vs. 31%), and among patients with Beta Thal (TM: 40%, TI: 49%, βE: 19%, HbH: 11%, HbH/CS: 5%, Hα: 0%) even after controlling for differences in age distribution. Prevalence of fractures increased with decreasing bone mass (AP spine Z or T scores measured by DXA) and increasing weight Z scores but was not associated with height or BMI Z scores. Prevalence of fractures was higher among patients treated for hypogonadism (59% vs. 26%) or hypothyroidism (65% vs. 32%) after controlling for age and gender. Traumatic fractures were most commonly reported (91%). Increased physical activity was associated with fractures among children ≤11y but not among other age groups. Rates of traumatic fractures among Beta Thal were higher than among other diagnosis (2.3/100 pt-yrs vs. 0.8/100 pt-yrs) after controlling for age. Rates of non-traumatic fractures among Beta Thal were elevated but not significantly higher than among other diagnosis (0.23/100 pt-yrs vs. 0.07/100 pt-yrs). 34% of patients reported bone pain during the 30 days prior to enrollment. Of those, 17% used prescription pain medications and an additional 36% used over-the-counter analgesics. The prevalence of bone pain increased with age, was higher in females (males: 28%, females: 40%), was higher in TM and Hα (TM: 40%, TI: 16%, βE: 19%, HbH: 37%, HbH/CS: 35%, Hα: 67%) and did not correlate with bone mass, height, weight and BMI Z scores or any reported endocrinopathies. In summary, fractures continue to occur frequently despite current treatment practices, especially among the older patients with Beta Thal. Bone pain remains a frequent complaint among the Thalassemia syndrome subjects.
RTP801 Is a Novel Retinoic Acid Responsive Gene Possibly Involved in Myeloid Differentiation.
Authors: Gery Sigal , Park Dorothy J. , Vuong Peter T. , Koeffler H. Phillip 
Published: April 2020

Abstract
Retinoic acid (RA) promotes terminal differentiation of both normal hematopoietic cells and acute promyelocytic leukemia (APL) blasts by transcriptional regulation of myeloid genes. To identify additional RA target genes, we used representational difference analysis (RDA) with RNA derived from a PML/RARα inducible U937 myeloid cell line. From this screen we identified a novel early responsive RA target gene, RTP801 (REDD1). Recent studies showed that RTP801 is a critical transducer of several cellular stress signals, including hypoxia and energy depletion, through the TSC-mTOR pathway. We show that All-trans retinoic acid (ATRA) induces RTP801 mRNA in AML cell lines in a dose- and time-dependent manner. ATRA regulation of RTP801 is direct and does not require protein synthesis. Inhibition of endogenous RTP801 in U937 cells by siRNA abrogates ATRA-induced dephosphorylatioin of 4E-BP1, a key mTOR substrate. Overexpression of RTP801 in these cells results in growth arrest and apoptosis. RTP801 is differently expressed during maturation of normal CD34+ cells, suggesting it is involved in this process. We performed a yeast two-hybrid screen using a leucocyte cDNA library and identified the myeloid-specific protease, neutrophil elastase, as a binding partner of RTP801. Taken together, RTP801 is a novel ATRA target gene possibly involved in ATRA-induced differentiation of myeloid cells.
Two Single Nucleotide Polymorphisms of the ETS2 Transcriptional Factor Gene Predispose Individuals to High-Risk Acute Myelogenous Leukemia (AML).
Authors: Lee Il-Kwon , Choi Jeong-Hwa , Kim Yeo-Kyeoung , Kim Hee Nam , Park Kyeong-Soo , Lee Je-Jung , Shin Myung Geun , Choi Chan , Kook Hoon , Hwang Tae Ju , Park Moo Rim , Jo Deog Yeon , Won Jong Ho , Kim Hyeoung-Joon 
Published: April 2020

Abstract
ETS2 (v-ets avian erythroblastosis virus E2 oncogene homolog 2) is a transcription factor located in the human chromosomal region 1q22.3 encoding a 56-kDa protein. In this study we carefully selected a set of haplotype-tagging SNPs (htSNP) and genotyped their frequencies in order to identify polymorphic variants that contributes to the inter-individual differences in susceptibility to disease phenotypes. Here we report polymorphisms of ETS2, a hematopoietic transcription factor gene is associated with increased risk to AML. Seven SNPs derived from genomic region of the ETS2 gene, rs1209953, rs3746882, rs2298560, rs457705, rs2070531, rs711 and rs5307 were genotyped to estimate allele frequency, haplotype block and linkage disequilibrium (LD) map. Among those rs711 and rs530 were shown to be associated with increased risk to AML with statistical significance. The odds ratio (OR) for rs711 and rs530 relative to wild type genotypes are 1.76 (95% C.I. 1.2–2.5, p=0.0019) and 1.67 (95% C.I. 1.3–2.2, p=0.0003) respectively. Cumulative frequencies of four common haplotypes are 72%, among which T-T-G-T-C-G-T was the most ancestral haplotype comprising 36% of total haplotypes. We also examined the possibility of haplotype association, but no association was found. When we compared LD map with LDs constructed from the International HapMap project, Korean LD map was similar to Japanese LD, but least similarity was shown with LDs from African(Yoruba in Ibadan, Nigeria). Since these two SNPs are located in the 3′ UTR region we simulated the change in secondary structure in silico of the 3′ UTR region with two variants sequence. Severe change in the secondary structure was observed in the rs530 containing domain suggesting this change might affects stability of mRNA. Real time Q-PCR and western blot revealed that expression of ETS2 decreased in a dosage-dependant manner, showing most abundant expression when homozygously T/T at rs530, least expression with the homozygous A/A and intermediate level of expression when the heterozygous genotype. Our results suggest that polymorphic variants in the 3′ UTR region predispose individual to high-risk AML by altering the secondary structure of mRNA.
Treatment of Graft Failure with Fludarabine (Flu), Antithymocyte Globulin (ATG) and a Second Allogeneic Stem Cell Transplantation (SCT).
Authors: Jabbour Elias J. , Shahjahan Munir , Rondon Gabriela , Anderlini Paolo , Giralt Sergio , Couriel Daniel R. , Champlin Richard E. , Khouri Issa F. 
Published: April 2020

Abstract
Failure to engraft after SCT is a life-threatening complication. In a pilot trial, we assessed the feasibility of a second SCT after conditioning with Flu and ATG. Primary graft failure was defined by the inability to achieve any donor cell engraftment and to sustain an absolute neutrophil count (ANC) &gt;0.5 x 109/l, for 3 consecutive days by day 28 after SCT. Secondary graft failure was defined as recurrent neutropenia with an ANC &lt; 0.5 x 109/l for at least 7 consecutive days. Between July 1998 and April 2003, nine patients (pts) with various hematological malignancies (chronic myeloid leukemia [CML] n=5, acute myeloid leukemia [AML] n=2, myelodysplastic syndromes [MDS] n=2) were prospectively studied. Their median age was 38 years (range, 33-75). Eight had a primary and one had a secondary graft failure after conditioning with Bu/Cy (N=3), Flu/Bu (N=1), Melphalan/Flu (N=3), and Cy/Thiotepa/TBI (N=2). Cultures for CMV, Parvo-virus and HSV-6 were all negative. Median time between the first and the second SCT was 54 days (range, 31–140 days). All pts received Flu 25 mg/m2 intravenously (IV)/day on days −5 to −1, and ATG 20 mg/kg/day IV on days −3, −2, −1. Transplantation was provided on day 0. Tacrolimus was used for graft-versus-host disease (GVHD) prophylaxis. Eight pts received their second SCT from the peripheral blood of same donor [matched siblings (sib) =3, one-antigen mismatched sib =2, two-antigen mismatched sibling =1, haplo-identical sibling=1] whereas one had a cord blood (CB) transplant. The median dose of CD34+cells infused was 8 x 106/kg. Three pts had early death and were not evaluable. Six other pts, including the one who received a CB, had engrafted with 100% donor chimerism. Five recovered an ANC&gt; 500 at a median of 18 days (range, 9–42 days). Complete disease response was documented in 4 pts including 3 with CML who achieved molecular response, and one with MDS. Three pts had grade 2, and three grade 3–4 acute GVHD. Median survival time of all pts was 7 months from their first SCT (range, 2–24 months). We conclude that Flu/ATG is a feasible regimen for second SCT as treatment for graft failure, allowing engraftment of donor hematopoiesis. GVHD was a major problem, and future studies should include more intense immunosuppressive prophylaxis.
Successful Engraftment of Autologous CD34+ Stem Cells after High-Dose Therapy and Fixed Dose (6 mg) Pegfilgrastim.
Authors: Marcacci Gianpaolo , Petti Maria C. , Ferrara Felicetto , Storti Sergio , D’Arena Giovanni , Palombi Francesca , Palmieri Salvatore , Giordano Giulio , Pinto Antonio 
Published: April 2020

Abstract
High-dose (HD) therapy plus Autologous Stem Cell Transplantation (ASCT) is a milestone treatment program for most hematologic malignancies. Daily subcutaneous injections of G-CSF (filgrastim/lenograstim) until ANC &gt; 500/μl are routinely administered following ASCT, in order to accelerate hematopoietic recovery and reduce neutropenic complications. Pegfilgrastim has been shown to have similar efficacy when compared to G-CSF for chemotherapy-induced neutropenia, but little is known about its use in the ASCT setting. We used a 6 mg fixed dose of Pegfilgrastim on day +4 following ASCT in 46 patients (22 M/24 F; median age 56 yrs; r 22-70 yrs) with multiple myeloma (25 pts) and relapsed or refractory Hodgkin’s and non-Hodgkin’s lymphoma (21 pts). Patients received peripheral CD34+ stem cells (median number 4.4 x 106/Kg; r 1.8 – 11.8) harvested after mobilizing chemotherapy (cytoxan, vinorelbine/cytoxan, R-IEV, IGEV, R-ICE) and G-CSF. Standard conditioning regimens (HD-Melphalan or BEAM) were used. Engraftment results were compared to those from a historical control group of 182 patients (median age 56 yrs; r 16-74 yrs) who had received HD-Melphalan or BEAM and ASCT (median CD34+ cells 7.6 x 106/Kg, r 1.8–4.6) supported by G-CSF (5 μg/kg/day from day +5 until ANC&gt;500/μl). Median number of days to ANC&gt;500/μl were comparable between the Pegfilgrastim (10, r 8-15) and G-CSF (11, r 7–22) groups, as well as the median number of days to PLT&gt;20,000/μl (Pegfilgrastim = 12, r 9–20 vs G-CSF= 12, r 7–29). Overall infectious rates, including FUO and documented infections, were of 48% and 39% for Pegfilgrastim and G-CSF groups, respectively (p=NS). Median number of days on i.v. antibiotics were 0 (r 0–18) and 6 (r 0–13) for the Pegfilgrastim and G-CSF groups, respectively. No significant differences in the incidence of bone pain, intensity of transfusion support and length of hospital stay were documented between the two groups. These data indicate that a fixed (6 mg) single-dose of Pegfilgrastim is safe and effective to accelerate engraftment after ASCT. No significant differences with G-CSF were apparent as to engraftment times and overall infectious complications. Growth factor costs were however in favor of Pegfilgrastim (Euro 690 vs 892 for a median of 10.5 G-CSF doses).
Hematopoietic Cell Transplantation as Therapy for Pediatric Patients with Isolated CNS Relapse.
Authors: Harker-Murray Paul , Tolar Jakub , Tan Ye , MacMillan Margaret L. , Wagner John , Orchard Paul J. 
Published: April 2020

Abstract
Treatment options for pediatric patients with isolated central nervous system (CNS) relapse of acute lymphoblastic leukemia (ALL) include intensive chemotherapy followed by craniospinal irradiation and hematopoietic stem cell transplantation (HSCT). However, there is little information regarding outcomes of HSCT in this situation. At the University of Minnesota 15 patients &lt;18 years of age underwent allogeneic HSCT for ALL with isolated CNS relapses between 1990 and 2004. Leukemic subtypes included B cell (7), pre-B cell (6), T cell (1), and ALL NOS (1). All patients were in remission at the time of transplantation; 9 patients were in CR2, 5 patients were in CR3, and 1 patient was in CR5. Median duration of CR1 in all patients was 21.9 months (range 8.5–57.7) with median time from diagnosis of ALL to CNS relapse 23.4 months (range 8.9–127.7) in all patients. For patients transplanted in CR2, the median duration of 1st CR was 16.2 months (range 8.5–30.1). For all patients, transplantation was performed following a relapse limited to the CNS. Stem cell sources were related in 8 cases (5 HLA-matched marrow, 2 mismatched marrow, 1 matched cord blood) and unrelated in 7 (3 mismatched URD marrow, 2 5/6 matched cord blood, 2 4/6 matched cord blood). Preparative regimens included total body irradiation (TBI) and cyclophosphamide (Cy) for 12 patients, and Cy, TBI, VP16 for 3 patients. Grade II-IV GvHD occurred in 7 patients (47%; 95% CI 21–72) and grade III-IV in 3 patients (20%; 95% CI 0–40) by day 100. All patients were alive 1 year following transplantation. With a median follow-up of 7 years (range 1 to 19.4), the estimated 5 year survival is 78% (95% CI 51–100%). Of the 2 patients that died, 1 transplanted in CR2 died of relapse, while another transplanted in CR2 died of ARDS. Both were recipients of related donor grafts. These data demonstrate hematopoietic stem cell transplantation is a viable therapeutic option for pediatric patients with isolated CNS relapse, and suggests that a larger multi-institutional analysis should be undertaken.