bluuebunny/crossref_metadata_2025_split huggingface dataset:
Invasive Fungal Infections in Pediatric Acute Lymphoblastic Leukemia: Incidence, Characterization, Outcome and Risk Analysis of Study ALL-BFM 2000
Authors: Mann Georg , Attarbaschi Andishe , Schrappe Martin , Möricke Anja , Bleckmann Kirsten , Alten Julia , Lehrnbecher Thomas , Zimmermann Martin , Niggli Felix 
Published: October 2019

Abstract
With achievable survival rates of above 90%, non-leukemic events gather a high proportion of treatment failure causes with infections forming the majority. We analysed the incidence and outcome of reported invasive fungal infections as serious adverse events (SAE according to NIH criteria) in study ALL-BFM 2000 with the aim to characterize risk factors to optimize antifungal prophylaxis and treatment. A total of 4867 patients with ALL were enrolled from August 1999 to May 2010. Analysis of (mandatory) SAE reporting revealed 144 cases (3%). Fungal infections related to hematopoietic stem cell transplantation were excluded. According to the EORTC/MSG classification 65 (1.3%) were proven, 53 (1.1%) probable/possible and 26 (0.5%) not classifiable. There were 19 (0.4%) deaths and 41 (0.8%) events were classified as life threatening according to FDA definition. Positive mycological results were available in 98 cases: Aspergillus ssp. in 72, Candida ssp. in 21, Mucor in 3, Rhizopus and Fusarium in 1 case each. Fatality occurred in 16 cases with Aspergillus (22%) and in 1 each of the other species. Out of 41 life-threatening infections 30 were due to Aspergillus, 5 to Candida and 4 to the other species. Regarding all fungal infections, there was a significantly rising risk with increasing age (7.2% >15 y, 4.8% 10-<15 and 2.1% >1-< 10y; p<0.001), significance of age-dependent differences remained conserved for the life-threatening and fatal infections. Additionally, female gender appeared to impose a significant higher risk (all fungal infections, 2.4 vs. 3.7%, p=0.005). With respect to the treatment phase, the risk of fungal events was highest during induction, especially in the case of delayed treatment response, and during intensive block chemotherapy in the high-risk arm. This study on a very large population of children with ALL demonstrates that invasive fungal infections represent an important cause of morbidity and mortality in this cohort, giving support to reflect prophylactic measures for patients at high risk in the future.

Disclosures
No relevant conflicts of interest to declare.
Breast Milk from Immune Thrombocytopenic Mothers Can Contain Anti Platelet Antibodies That Are Associated with Persistent Thrombocytopenia in Neonates
Authors: Sharon Nehama , Rosenberg Nurit , Seligsohn Uri , Simmonds Aryeh , Shiff Yakov , Schechter Yaakov , Hausner Hagit 
Published: October 2019

Abstract
Purpose: Maternal immune thrombocytopenic purpura (ITP) accounts for 5% of all cases of pregnancy associated thrombocytopenia and is a common cause of neonatal thrombo­cytopenia. One of the common mechanism involves transfer of IgG autoantibodies against platelet receptors which are found in the blood samples of affected patients. The neonatal thrombocytopenia usually subsides within 2 months. The autoantibodies are often of the IgG type and therefore can cross the placenta and cause fetal and/or neonatal thrombocytopenia. Recently we observed persistence of neonatal ITP which disappeared following discontinuation of breast feeding. The aim of our current work was to discern whether breast milk of mothers with ITP contains anti-platelet antibodies and whether these antibodies may be the cause for persistent neonatal ITP.
Methods: Breast milk samples were collected from 12 women with ITP. Six of them were thrombocytopenic during pregnancy and their neonates also had thrombocytopenia. The remaining 6 mothers had a history of ITP but not during the current pregnancy, and neither did their neonates. As controls, breast milk from 8 healthy women was also examinied.
The presence of anti-platelet antibodies were evaluated by incubating washed platelets from healthy donors with breast milk or extracted milk – Ig. The type of immune globulin was defined by flow cytometry using fluorescence conjugated anti-human IgA, IgG or total Ig antibodies. To prove that the antibodies were against an antigen that is platelet specific and not against HLA epitopes, we also tested the samples on cultured cells expressing the fibrinogen receptor, αIIbβ3, and compared the results to mock cells (transfected with empty vectors).
Results: In the cases of women with active ITP, 3 were positive for anti-platelet antibodies, 2 were inconclusive and one was negative. In the mothers with a history of ITP, 1 was positive, 1 was inconclusive and 4 were negative. No anti-platelet antibodies were found in breast milk of healthy women. In all 6 cases of active ITP, the cell cultured assay for the fibrinogen receptor αIIbβ3 was positive, indicating that there were anti platelet specific antibodies in their milk. Of the 6 neonates of mothers with active ITP, 4 of them required treatment with oral steroids, and the average time to resolution of thrombocytopenia was 3.5 months.
Conclusion: This study demonstrates that breastmilk of women with active ITP contains anti platelet specific antibodies. The presence of these antibodies demonstrated an association with persistant and prolonged neonatal thrombocytopenia.

Disclosures
No relevant conflicts of interest to declare.
Tyrosine Kinase-Directed Ubiquitin Ligases Cbl and Cbl-b Enforce Hematopoietic Stem Cell Quiescence By Negatively Regulating c-Kit and FLT3
Authors: An Wei , Nadeau Scott , Mohapatra Bhopal , Feng Dan , Zutshi Neha , Storck Matthew , Band Vimla , Band Hamid 
Published: October 2019

Abstract
Maintenance of quiescent hematopoietic stem cells (HSCs) is essential for life-long hematopoiesis. A prominent category of HSC quiescence regulators that determine HSC fate by directly interacting with niche-derived growth factors are receptor tyrosine kinases (RTKs). Cbl and Cbl-b are E3 ubiquitin ligases that are directed to activated tyrosine kinases and negatively regulate a number of cellular activation pathways. Previously, we established a conditional Cbl and Cbl-b double knockout (DKO) mouse strain using MMTV-Cre to delete floxed Cbl on a Cbl-b-null background, and identified that Cbl and Cbl-b function redundantly in controlling the growth factor-induced proliferation of HSCs. These DKO mice developed a rapidly fatal myeloproliferative disorder (MPD) accompanied by expansion of the HSC compartment. However, how the negative regulatory functions of Cbl-family proteins are integrated into HSC homeostatic program and the mechanistic basis for their role remain unknown.
Here, we utilize mouse models to examine the functional role of Cbl and Cbl-b in regulating HSCs and its potential mechanistic basis. Transplant analyses revealed that DKO HSCs are the disease-initiating cells. However, in vitro serial colony-forming assays showed that DKO HSCs possess a reduced colony-forming ability despite their hyper-proliferative status. Cell cycle analyses demonstrated a smaller pool of quiescent long-term HSCs in DKO mice. Non-responder assays in vivo showed a reduced frequency of functional HSCs in the DKO LSK compartment and serial HSC transplantation demonstrated compromised reconstitution ability of DKO HSCs, especially at the 2nd round of transplantation. Mechanistically, DKO HSCs exhibit sustained signaling in response to c-Kit and FLT3 ligands, especially via p-Akt but also p-Erk and p-S6. The ligand-induced cell surface c-Kit and FLT3 receptor downregulation was slower in DKO HSCs. Furthermore, while c-Kit and FLT3 ligands promote higher proliferation of DKO bone marrow cells, this hyper-proliferation leads to loss of colony-forming potential that is significantly reversed by respective kinase inhibitors.
Together, our data reveal a novel and physiologically essential role of Cbl and Cbl-b in the enforcement of HSC quiescence and protection against exhaustion by fine-tuning the signaling pathways downstream of tyrosine kinase-coupled receptors such as c-Kit and FLT3. These findings could have significant implications for hematological neoplasms associated with mutations of Cbl.

Disclosures
No relevant conflicts of interest to declare.
The P2Y6-AMPK Pathway Triggers Autophagy during CSF-1-Induced Human Monocyte Differentiation and Is a Potential Target in CMML
Authors: Obba Sandrine , Hizir Zoheir , Selimoglu-Buet Dorothée , Boyer Laurent , Pfeifer Anja , Hamouda Mohamed-Amine , Goncalves Diogo , Cerezo Michael , Marchetti Sandrine , Rocchi Stephane , Droin Nathalie , Robert Guillaume , Luciano Frederic , Robaye Bernard , Viollet Benoit , Legros Laurence , Solary Eric , Auberger Patrick , Jacquel Arnaud 
Published: October 2019

Abstract
Autophagy is the process by which superfluous or damaged macromolecules or organelles are degraded by the lysosome. Pharmacological and genetic evidence indicate that autophagy plays pleiotropic functions in cellular homeostasis, development, survival and differentiation. The differentiation of human blood monocytes into macrophages is a caspase-dependent process when triggered ex vivo by M-CSF. We have previously shown, using pharmacological inhibitors, siRNA approaches and Atg7-/- mice, that autophagy initiated by ULK1 is required for proper CSF-1-driven differentiation of human and murine monocytes. We have also unraveled a role for autophagy in macrophage acquisition of phagocytic functions. Here, we determine that the CaMKKb-AMPKa1-ULK1 pathway is required for CSF-1-induced autophagy and human monocyte differentiation. We reveal that this pathway links P2Y6 to the induction of autophagy, and we decipher the signalling network that links the CSF-1 receptor to P2Y6-mediated autophagy and monocyte differentiation. Importantly, we show that the physiological P2Y6 ligand UDP and the specific P2Y6 agonist MRS2693 restore normal monocyte differentiation through re-induction of autophagy in primary myeloid cells from chronic myelomonocytic leukemia (CMML) patients. Collectively, our findings highlight an essential role for P2Y6-mediated autophagy during differentiation of human monocytes and pave the way for future therapeutic interventions for CMML.

Disclosures
No relevant conflicts of interest to declare.
Mice with a Mutation in the Mdm2 Gene That Interferes with MDM2/Ribosomal Protein Binding Develop Bone Marrow Failure
Authors: Kamio Takuya , Gu Bai-wei , Olson Timothy S. , Zhang Yanping , Mason Philip J , Bessler Monica 
Published: October 2019

Abstract
MDM2, an E3 ubiquitin ligase, is an important negative regulator of p53. In turn the MDM2 gene is a transcriptional target of p53, forming a negative feedback loop that is important in cell cycle control. It has recently become apparent that the ubiquitination of p53 by MDM2 can be inhibited by the binding of some ribosomal proteins, including RPL5 and RPL11, and that the resulting increase in p53 levels may be important in the red cell aplasia seen in DBA and in 5q- MDS. DBA and 5q- MDS are associated with inherited (DBA) and acquired (5q-MDS) haploinsufficiency of ribosomal proteins. A mutation in MDM2 causing a C305F amino acid substitution blocks the binding of ribosomal proteins. Mice harboring this mutation, retain a normal p53 response to DNA damage, but lack the p53 response to perturbations in ribosome biogenesis.
While studying the interaction between RP haploinsufficiency and the Mdm2C305F mutation we inadvertently noticed that Mdm2 C305F/ C305F mice had perturbed hematopoiesis. These mice had a mild macrocytic anemia with reticulocytosis and high erythropoietin levels. In the bone marrow, these mice showed a significant decrease compared to wildtype (WT) littermates in Ter119+ cells, while no decrease in the number of immature erythroid cells (Ter119+CD71+) was found in the spleen, which showed significantly increased hematopoiesis. In methyl cellulose cultures BFU-E colonies from the mutant mice were slightly reduced in number and there was a significant reduction in CFU-E colony numbers in mutant mice compared with WT controls(p < 0.01). Further investigation revealed that there was a decrease in Lin-Sca-1+c-Kit+(LSK)cells, accompanied by significant decreases in short-term hematopoietic stem cells(ST-HSC) (p < 0.05) and multipotent progenitor(MPP) cells(p < 0.05).
These results suggest that control of the cell cycle through interactions between ribosomal proteins and MDM2 is important in the regulation of normal hematopoiesis as well as in the pathogenesis of 5q- MDS and DBA.

Disclosures
No relevant conflicts of interest to declare.
Low Toxicity Profile of the Combination of Bendamustine Plus Rituximab (BR) in Elderly FRAIL Patients with Newly Diagnosed DLBCL
Authors: Spina Michele , Luminari Stefano , Salvi Flavia , Passamonti Francesco , Fabbri Alberto , Vitolo Umberto , Cabras Maria Giuseppina , Miglino Maurizio , Merli Francesco , Fattori Pier Paolo , Liberati Anna Marina , Zaccaria Alfonso , Tosi Patrizia , Ciancia Rosanna , Pesce Emanuela Anna , Storti Sergio 
Published: October 2019

Abstract
Introduction: R-CHOP is the gold standard for the treatment of elderly patients with DLBCL. However, unfit and frail patients frequently do not qualify for CHOP-based chemotherapy. Alternatives are an urgent medical need. Bendamustine plus rituximab (BR) has been established as a standard treatment of indolent lymphomas and preliminary data have shown a promising activity in DLBCL, both in the relapsing and upfront setting.
Methods: Within the Fondazione Italiana Linfomi (FIL), we started a phase II study (R-BENDA frail study, EUDRACT2011-001421-24) in elderly patients (>70 years) with a newly diagnosed DLBCL not suitable for R-CHOP-based chemotherapy. All patients were evaluated according to ADL, IADL and CIRS-G and were considered FRAIL if the following criteria were meet: in patients aged 70-80 ADL<4 or IADL<5 or one grade 3 comorbidity or >8 grade 2 comorbidities; in patients older than 80 years ADL>5 or IADL>6 or 5-8 grade 2 comorbidities. Patients received bendamustine at a dose of 90 mg/m2 daily on days 1 and 2 of each 28-day cycle along with rituximab on day 1 for up to 6 cycles.
Results: From February 2012 to February 2014, 49 patients were enrolled in 24 Italian centers. The majority (57%) were male and 57% had stage III-IV with 41% elevated LDH. The median age was 82. Overall, 83% of the planned cycles were delivered without dose reduction or delay; grade 3/4 neutropenia was reported in 25% of cycles followed by anemia 21%, and thrombocytopenia 20%. One case of febrile neutropenia was observed. Grade 3-4 non-hematological toxicity was mild and reported in 6% of cycles including 3 episodes of cardiovascular events and 7 other cases of different toxicities (one creatinine increase, one fatigue, one bleeding, one peripheral neurotoxicity, one hyponatriemia, one hyperglycemia and one liver toxicity). Two deaths during treatment have been observed (cardiac failure and sudden death). At the interim analysis (23 patients) the overall response rate was 56% with a complete response rate of 39%.
Conclusions: Combination therapy with BR demonstrates low toxicity profile in this high risk population. The promising results on activity can encourage clinicians to considered BR for the treatment of FRAIL elderly patients with DLBCL not eligible for R-CHOP.

Disclosures
No relevant conflicts of interest to declare.
Initial Results of an Ex Vivo Microfluidic Cis-Coculture Csra to Predict Response for Myeloma Patients
Authors: Pak Chorom , Callander Natalie S , Young Edmond WK , Titz Benjamin , Kim KyungMann , Chng Kenny , Miyamoto Shigeki , Beebe David J 
Published: October 2019

Abstract
In vitro chemosensitivity and resistance assays (CSRAs) test primary tumor cells’ response to chemotherapeutic drugs. The goal of CSRAs is to potentially direct therapy based upon in vitro response. This is in contrast to empiric therapy of cancer patients where therapy is based on clinical trial evidence and the likelihood of patient response. However, most previous CSRAs have been unsuccessful; this may be because they employ tumor cells in mono-culture. increasing evidence indicates that heterogeneity in tumor cell biology and microenvironment and the interaction between the two play essential roles in regulating drug response. In addition, many of these assay and culture systems require more tumor cells per condition than can be obtained from every patient. Furthermore, coculture systems in the past often cultured tumor and non-tumor cells from different patients (trans-coculture). Therefore, a CSRA capable of being performed for all patients while incorporating both tumor cells and non-tumor microenvironmental cells from the same patient is needed.
Here, by using a microfluidic ex vivo system requiring only thousands of cells per condition, we analyzed patient CD138+ multiple myeloma (MM) cells in either microfluidic mono-culture (MicroMC) or cis-coculture (MicroC3) with their own CD138- non-tumor mononuclear cells. The MM CD138+ cells were then exposed to varying doses of bortezomib, a clinical proteasome inhibitor, for 24 hours. An in-house software program, J’experiment, was used to calculate live fractions of the tumor cells. Because plasma concentrations of bortezomib peak at 100 nM, the change in live fraction was calculated from the 0 and 100 nM dose of bortezomib. Using k-means and Gaussian mixture clustering techniques, MicroC3 responses could be grouped into two distinct data clusters which correctly identified 17/17 patients as either clinically responsive (7) or non-responsive (10). On the other hand, responses measured in MicroMC could not be unambiguously separated into clinical response groups. Thus, MicroC3 accurately identified MM patient responses as either responsive or non-responsive to bortezomib-containing therapy. Further development of MicroC3 as a CSRA with the ability to rapidly identify chemosensitive or resistant cancer patients will enable more personalized therapeutic decisions.

Disclosures
Beebe: Bellbrook Labs, LLC: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties.
Targeting HDAC6 Is a Novel Approach to Augment the Therapeutic Benefit of Bromodomain Inhibition in Multiple Myeloma
Authors: Carew Jennifer S. , Espitia Claudia M. , Zhao Weiguo , Kelly Kevin R. , Nawrocki Steffan T. 
Published: October 2019

Abstract
Multiple myeloma (MM) is a plasma cell disease that represents the second most common adult hematologic malignancy in the United States. Advances in the treatment of MM, including the development of proteasome inhibitors have improved clinical outcomes. However, many patients fail to respond to these newer agents or relapse after initial response. Constitutive activation of the MYC oncogene is a frequent pathogenic event in MM that drives disease progression making it an ideal therapeutic target. Recent studies suggest that inhibition of bromodomain and extra terminal (BET) protein family members including BRD4 decreases the expression of c-MYC and other key oncogenic factors such as BCL-2 and displays significant activity against MM. Here, we demonstrate that shRNA-mediated knockdown of BRD4 or treatment with the BRD4 antagonist JQ1 decreased the expression of c-MYC, BCL-2, and BCL-XL, diminished cell viability, disrupted clonogenic survival, and triggered apoptosis in a panel of MM cell lines. Subsequent assays conducted in MM cell lines confirmed a strong reduction in MYC levels and activity following treatment with JQ1 along with consistent increases in the expression of genes regulated by BRD4 including CDKN1A and HEXIM1. Interestingly, gene expression profiling assays revealed that the histone deacetylase HDAC6 was also highly significantly elevated in all MM cell lines and primary patient specimens treated with JQ1. Based on its ability to alter cellular survival capacity, we hypothesized that HDAC6 induction may reduce the anti-myeloma activity of JQ1. To test this hypothesis, we utilized shRNA-mediated knockdown of HDAC6, the pan-HDAC inhibitor vorinostat, and the HDAC6-selective inhibitor ACY-1215 (rocilinostat) and evaluated the impact of each on the anti-MM effects of JQ1. Abrogation of HDAC6 activity synergistically enhanced the activity of JQ1 in a panel of MM cell lines. These effects were also observed in primary CD138+ cells obtained from patients with MM in a manner that was not affected by prior treatment history. The increased efficacy of these therapeutic combinations was associated with apoptosis induction as evidenced by enhanced caspase-3 cleavage and further reductions in c-MYC expression. These data suggest that HDAC6 induction may represent a key mechanism that promotes drug resistance and/or limits the efficacy of bromodomain inhibitor therapy. Our collective findings indicate that abrogation of HDAC6 activity with ACY-1215 or vorinostat is a novel and promising approach to augment the efficacy of bromodomain inhibitors for MM that warrants further investigation.

Disclosures
No relevant conflicts of interest to declare.
Increased Levels of Thrombopoietin and IPF in Patients with Iron Deficiency Anemia
Authors: Kawasugi Kazuo , Yamamoto Tadashi , Shirafuji Naoki , Oka Yoko 
Published: October 2019

Abstract
Background
Thrombocytosis has been reported in about 50% of patients with iron deficiency anemia (IDA). However, the mechanism of the increase in the number of platelets is unknown. To investigate the relationship of endogenous thrombopoietin (TPO) and circulating platelet counts, we measured the plasma levels of TPO, immature platelet fraction (IPF) and erythropoietin ( EPO ) in 25 patients with IDA.
Patients and methods
Patients with IDA (newly diagnosed) were recruited from February 2013 through March 2014 in Teikyo University School of Medicine. TPO (Immuno-Biological Laboratory, Japan), was determined by an EILSA. IPF was measured on the Sysmex XE2100. EPO (Roch Diagnostic Japan) was determined by an EILSA.
Results and Conclusions
The number of platelets was increasing in the half patients with IDA in this study. Peripheral blood samples for measuring IPF were obtained from 300 healthy adult controls (160 women and 140 men) and 20 patients with IDA, consisting of 19 women and 6 men with age ranging from 16 to 75 years. The etiology of iron deficiency was gastrointestinal (GI) blood loss, menometrorrhagia, previous GI surgery, and low dietary iron intake. The mean absolute-IPF was significantly higher for IDA patients than for healthy control (8193±571 vs. 4254±193 p＜0.05). The endogenous levels of TPO were significantly elevated in patients with IDA (216.4±41 pg/ ml) as compared with normal controls (116.5±23 pg/ml). Also, The endogenous levels of EPO were significantly elevated in patients with IDA as compared with normal controls. There was a significant inverse correlation between serum Fe levels and platelet counts (r=0.551, p＜0.05). Also, a positive correlation (r=0.311, p＜0.05) between platelet counts and endogenous level of TPO was found. Moreover, there was a significant inverse correlation (r=-0.458, p＜0.05) between Hb and TPO. These results suggest that TPO is active regulator, in thrombopoiesis and megakaryocytopoiesis in patients with IDA. Also, it appears there is relationship between erythropoiesis and TPO.

Disclosures
No relevant conflicts of interest to declare.