bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inflammasome Activation Promotes Deep Vein Thrombosis through Pyroptosis
Authors: Zhang Yan , Zhang Guoying , Jian Cui , Wu Congqing , Mackman Nigel , Smyth Susan , Wei Yinan , Li Zhenyu 
Published: November 2019

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), is one of the most common causes of cardiovascular death worldwide. Monocytic cells (including monocytes/macrophages) and their derived tissue factor have been reported to play important roles in the development of DVT. However, the mechanism by which monocytes contribute to the development DVT is not well elucidated. In this study, we reported a critical role of inflammasome activation and pyroptosis in the development of DVT. Using a flow restriction-induced mouse DVT model in the inferior vena cava, we show that deficiency of caspase-1 protected against flow restriction-induced DVT. Inflammasome activation leads to interleukin (IL)-1b and IL-18 maturation/release and pyroptosis. Recent studies show that caspases-1 cleaves Gasdermin D (GSDMD) and triggers pyroptosis-a form of programmed cell death with similar morphology to necrosis. We tested the hypothesis that GSDMD-dependent pyroptosis drives inflammasome-induced coagulation and DVT using Gsdmd-/- mice. Indeed, flow restriction-induced DVT was inhibited by GSDMD deficiency. After induction of DVT, fibrin was deposited in the vein as detected by Western blot with a monoclonal antibody that specifically recognizes mouse fibrin, which were inhibited in the caspase-1 deficient mice and GSDMD deficient mice. IL-1b was also increased in tissue of vein following induction of DVT, which was inhibited by caspase-1 or GSDMD deficiency. Following inflammasome activation, pyroptotic macrophages release tissue factor (TF), an essential initiator of coagulation cascades. Consistently, flow restriction-induced DVT was flow restriction-induced DVT inhibited in inducible TF deficient mice. Our data reveal a critical role of inflammasome activation and pyroptosis in the development of DVT.

Disclosures
No relevant conflicts of interest to declare.
LSD1 Inhibitor 4SC-202 Inducing Apoptosis in Myelodysplastic Syndrome Cells Via NF-κb-HO-1 Pathway
Authors: Wang Weili , Zhang Zhaoyuan , Kuang Xingyi , Wang Jishi 
Published: November 2019

Aims: Human histone lysine-specific demethylase 1(LSD1) inhibit gene transcription and thereby block myeloid differentiation, apoptosis and cell cycle in AML. 4SC-202, a novel inhibitor of LSD1, is potential therapeutic agent for treating Myelodysplastic syndrome, while its mechanism of action remains unclear.
M ainly method : In the study, LSD1 and HO-1 gene expression were detected in MDS/AML patients. After MDS cell line SKM-1 was treated with 4SC-202, cell viability, apoptosis and cell cycle were detected by CCK-8 or FACS. Lastly, western blotting analyzed that the agent caused the change of the related cellular function protein in SKM-1 cells.
K ey findings: We found that LSD1 and HO-1 were overexpression in MDS/AML patients. LSD1 inhibitor 4SC-202 inhibited cell viability. The agent induced apoptosis by up-regulated BAX and cleaved caspase3/9 as well as down-regulated BCL-2, arrested cell cycle in the G2/M phase by down-regulated CDK1 and up-regulated p21, as well as inhibited activation of the NF-κB pathway and decreased HO-1. LSD1 and HO-1 expression were decreased after exposure with the NF-κB inhibitor OBY11-7082. Silencing LSD1 by LSD1 siRNA hardly caused apoptosis in SKM-1 cells, while the combination of Bay11-7082 and silencing LSD1 significantly decreased LSD1 and HO-1 expression and further increased apoptosis. While up-regulated HO-1 significantly limited the 4SC-202-induced down-regulation of BCL-2, up-regulation of cleaved caspase 3/9 and suppressed activation of NF-κB pathway as well as thereby attenuated the agent efficacy.
S ignificant : In conclusion, LSD1 inhibitor 4SC-202 induced apoptosis through the NF-κB-mediated HO-1 pathway. LSD1 might be a potential target for the treatment of MDS.

Disclosures
No relevant conflicts of interest to declare.
Cellular and Molecular Architecture of Hematopoietic Stem Cells and Progenitors in Genetic Models of Bone Marrow Failure
Authors: Heidemann Stephanie C. , Bursic Brian , Zandi Sasan , Li Hongbing , Klaassen Robert J , Abish Sharon , Rayar Meera , Breakey Vicky R. , Moshiri Houtan , Dhanraj Santhosh , de Borja Richard , Shlien Adam , Dick John E. , Dror Yigal , Abelson Sagi 
Published: November 2019

Inherited bone marrow failure syndromes (IBMFSs) such as Fanconi Anemia (FA) and Shwachman-Diamond syndrome (SDS) feature progressive cytopenia and a risk of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Using deep immunophenotypic analysis of hematopoietic stem cells (HSCs) and early progenitors in bone marrow samples from 13 FA/SDS patients without MDS/AML and 6 healthy controls, we revealed relative survival of progenitors that phenotypically resembled granulocyte-monocyte progenitors (GMP) in the patients. In contrast, HSCs, multipotent progenitors, common myeloid progenitors and megakaryocyte-erythroid progenitors were remarkably reduced in FA/SDS patients compared to controls. Whole exome and targeted sequencing of GMP-like cells in leukemia-free patients revealed a prominently higher mutation load in FA/SDS patient samples than in healthy controls. Patient samples also manifested molecular changes that are characteristic of AML: increased G>A/C>T variants, decreased A>G/T>C variants, increased trinucleotide mutations at Xp(C>T)pT, decreased lower mutation rates at Xp(C>T)pG sites compared to other Xp(C>T)pX sites and enrichment for cancer signature 1. AML cells have previously been reported as commonly harboring this cancer signature. Potential pre-leukemic targets in the GMP-like cells from FA/SDS patients included SYNE1, DST, HUWE1, LRP2, NOTCH2 and TP53. Serial analysis of GMPs from a SDS patient, who progressed to AML revealed a gradual increase in mutational burden, enrichment of G>A/C>T signature and emergence of new clones. Interestingly, the molecular signature of marrow cells from two FA/SDS patients with AML was similar to that of FA/SDS without transformation. The predicted founding clones in SDS-AML harbored mutations in several genes including TP53, while in FA-AML the mutated genes included ARID1B and SFPQ. In conclusion, we described an architectural change in the hematopoietic hierarchy of FA/SDS with remarkable preservation of GMP-like populations harboring unique mutation signatures. GMP-like cells might represent a cellular reservoir for clonal evolution.

Disclosures
No relevant conflicts of interest to declare.
Classification and Prognosis of Central Nervous System Involvement in Erdheim-Chester Disease
Authors: Cohen-Aubart Fleur , Idbaih Ahmed , Galanaud Damien , Law-Ye Bruno , Emile Jean-François , Charlotte Frédéric , Donadieu Jean , Amoura Zahir , Haroche Julien 
Published: November 2019

Background: Erdheim-Chester disease (ECD) is a non-Langerhans cell histiocytosis, characterized by the infiltration of tissues by foamy CD68+CD1a- histiocytes, with 1500 known-cases since 90 years. Mutations activating the MAPK pathway are found in more than 80% of ECD patients, mainly the BRAFV600E in 57 to 70%. Central nervous system (CNS) involvement during ECD lead to significant morbidity and mortality. We assessed CNS manifestations in a French cohort of 253 ECD patients. Since 2012, close to 200 patients worldwide with multi-systemic and refractory ECD (e.g. heart and/or CNS involvements) have benefited from BRAF and MEK inhibitors, which have proven highly beneficial.
Methods: CNS manifestations were determined by clinical examination and brain and/or spine magnetic resonance imaging (MRI). Targeted therapy efficacy was assessed using physician and radiologist global assessment.
Results: Ninety-seven (38%) among the 253 of the whole cohort of ECD patients had CNS involvement. CNS involvement was significantly associated with a younger age at diagnosis (mean 55.5 years) and at symptoms onset (mean 50.5 years), and also with the presence of the BRAFV600E mutation (in 77% of cases), xanthelasma (34%), and diabetes insipidus (36%). Median survival among patients with CNS involvement was significantly lower than in ECD patients without CNS involvement (124 months versus 146 months, p=0.03). Seventy-four CNS MRI were centrally reviewed, corresponding to 3 patterns: tumoral in 66%, degenerative in 50%, and vascular in 18%. Targeted therapy (BRAF and/or MEK inhibitors) was associated with improvement of symptoms in 43% of patients, and MRI improvement in 45%.
Conclusions: CNS manifestations are typically associated with a poor prognosis in ECD. Three distinct patterns may be recognized: tumoral, degenerative, and vascular. Targeted therapy leads to clinical and/or imaging improvement in almost 50% of patients.

OffLabel Disclosure:
Targeted therapies such as BRAF inhibitor (vemurafenib) and MEK inhibitor (cobimetinib) are used in severe histiocytosis in EU but are off label
Perception of Dentists and Dental Hygienists in Saudi Arabia about Bleeding with Dental Procedures in Patients Using Antithrombotic Medications
Authors: Alsheef Mohammed Abdullah , Aljohany Sarah , Gray Jenny , Zaidi Abdul Rehman Z. , Kullab Ghaydaa Juma 
Published: November 2019

Background:
Antithrombotic medications are frequently used for the prevention of certain conditions such as venous thromboembolism (VTE). A major complication of treatment with antithrombotic is the risk of hemorrhage, especially after specific dental procedures.
Objectives:
This study was conducted to measure the knowledge of dentists and hygienists in Saudi Arabia about treating patients who are receiving new oral anticoagulants (NOACs) and determining if dentists and hygienists are treating patients according to international guidelines.
Methods:
Study design: An English language questionnaire was piloted and then revised and distributed amongst various dental institutions within Riyadh, Saudi Arabia.
Study Subjects: 302 participants (Dentists 94.7% and dental hygienists 5.3%) working within Saudi Arabia, 58.3 were males, and 41.7% were females. 30.5% of the subjects' experience was between 5 and 10 years.
Inclusion criteria: Dentists and hygienists who are practicing in Saudi Arabia during the defined study period and willing to participate.
Results:
It appears that there is still much confusion over-treating patients on antithrombotic medications, not only with the NOACs (i.e. Rivaroxaban, Dabigatran, Apixaban) but even with the more established medications, such as Warfarin and Aspirin; only approximately 30% of respondents were able to correctly respond to the appropriate method of treating patients receiving these medications. A large number of respondents stated that they did not know how to treat or would not treat patients on these antithrombotic medications (29.8% - 89.2%) which is very concerning, considering the large number of patients who are receiving antithrombotic medications.
Conclusion:
The familiarity of dentists and dental hygienists with the NOACs is very poor compared to the more established antithrombotic. Therefore, dental professionals need to be made more aware of the NOACs in order to facilitate proper and timely management.
Figure

Disclosures
No relevant conflicts of interest to declare.
JAK2V617F Hematopoietic Stem and Progenitors Are More Resistant to Chronic Blockage of IL-10 Signaling in a Murine Model of Myeloproliferative Neoplasms
Authors: Lai Hew Yeng , Trieu Tiffany , Han Tiffany , Brooks Stefan , Craver Brianna , Ramanathan Gajalakshmi , Fleischman Angela G. 
Published: November 2019

Rationale:
Chronic inflammation is a key feature of Myeloproliferative Neoplasm (MPN), inflammation drives symptom burden and disease progression. We have found that monocytes from MPN patients persistently produce Tumor Necrosis Factor-alpha (TNF) following Toll-like receptor stimulation due to dampened Interleukin 10 (IL-10) receptor signaling which usually serves to negatively regulate TNF production (Lai et al, 2019). Chronic inflammation leads to hematopoietic stem cell (HSC) exhaustion, and IL-10 plays an important role in HSC self-renewal (Kang et al, 2007).
JAK2V617Fknock-in HSC do not have a selective advantage over wild-type cells in competitive repopulation assays, this suggests that JAK2V617FHSC gain a selective advantage only under specific circumstances. Here, we investigate whether blockade of IL-10 signaling allows JAK2V617F HSC to gain a selective advantage over wild-type cells. We hypothesize that blocking IL-10 signaling impairs wild-type but not JAK2V617Fmutant HSC and thereby allowing JAK2 V617Fmutant cells to expand.
Results:
We used competitive transplantation to assess the impact of blocking IL-10 signaling on the selective advantage of JAK2V617Fversus wild-type HSC. We transplanted equal numbers of whole bone marrow cells from wild-type (CD45.1) and JAK2 V617F(CD45.2) mice into lethally irritated recipients (CD45.1/2). At day 60 post transplantation we injected mice intraperitoneally with 0.1mg IL-10R blocking antibody (n=5) or PBS (n=4) weekly. The relative contribution of JAK2V617Fcells to donor derived peripheral blood leukocytes (n=4) decreased over time (Figure 1A) in the PBS group. In contrast, the relative contribution of JAK2V617Fcells increased after 120 days in the IL-10R blocking antibody group (Figure 1A).
Mice were sacrificed at 186 days post-transplant to assess spleen size and quantify hematopoietic stem and progenitor cells. Mice treated with IL-10R blocking antibody had larger spleens than the PBS group (Figure 1B). The LKS (linnegc-kit+Sca-1+), which contains hematopoietic stem and progenitor cells, was expanded in the mice treated with IL-10R blocking antibody (Figure 1C). The relative contribution of JAK2V617Fcells in the LKS compartment (Figure 1D) as well as whole bone marrow (Figure 1E) was higher in the IL-10R blocking antibody group as compared to the untreated group. Bone marrow from these mice were used for secondary transplants to functionally assess HSC fitness, results are forthcoming.
Conclusions:
In vivo blockade of IL-10R signaling increases the competitive ability of JAK2V617Fmutant cells. Spleen size is also augmented with IL-10R blockade, likely a reflection of an increase JAK2V617Fmutant cell burden. This suggests that defects in IL-10 signaling may be contributing to expansion of the mutant cells.

Disclosures
Fleischman: incyte: Speakers Bureau.
Glucocorticoids Regulate the Splicing Factor MBNL1, a Potential Control Point for B-Cell Specification
Authors: Pufall Miles A. , Fang Mimi , Bradley Robert K. , Guo-Liang Chew , Lanier Ross , Tasian Sarah K. 
Published: November 2019

Glucocorticoids, such as dexamethasone and prednisone, are mainstays in the treatment of lymphoid malignancies and autoimmune diseases. To understand the mechanism of how glucocorticoids induce cell death, we integrated a comprehensive, genome-wide shRNA screen with differential gene expression analysis in B-cell acute lymphoblastic leukemia (B-ALL). In addition to activating pro-apoptosis genes and repressing anti-apoptosis genes, we found that repression of B-cell development genes contributes to dexamethasone-induced cell death in B-ALL. Similarly, elevated glucocorticoid levels brought on by stress in stroke victims causes lymphocytopenia by inducing of apoptosis in immature B-cells, but not hemopoietic stem cells or mature B-cells. Additionally, chronic stress has been associated with immune suppression and increased risk for autoimmune disease. Together these findings suggest that glucocorticoids play a normal role in B-cell development, and that elevated glucocorticoid levels in response to stress can alter that development.
A control point in this mechanism may be MBNL1. MBNL1 is a sequence-specific RNA binding factor that alters mRNA splicing, stability, and localization. In this work, we show that glucocorticoid suppression of MBNL1 contributes to induction of cell death in B-ALL. Deletion of MBNL1 by CRISPR/Cas9 in the B-ALL cell line NALM-6 induces accumulation and depletion of mRNA levels for hundreds of genes. A large number of B-cell specification genes, including CD19, CD79A, SPI1, and LEF1, are repressed upon MBNL1 deletion, whereas the most highly activated gene is CD34, which is a marker for the less mature lymphoid progenitor cells. Depletion of MBNL1 also changed the splicing of B-cell development genes, including quantitative depletion of LEF1 exon 6. These data suggest that depletion of MBNL1 induces de-differentiation of B-cell precursors. Consistent with this model, an analysis of gene expression in differentiating B-cells revealed a rapid elevation of MBNL1 expression during B-cell specification (after the lymphoid precursor stage), and a concomitant repression of CELF2, an RNA-binding splicing factor that has been shown to oppose MBNL1. We therefore propose that glucocorticoids play a physiological role in B-cell development by restraining B-cell specification through repression of key genes, including MBNL1.
Figure

Disclosures
Tasian: Aleta Biotherapeutics: Membership on an entity's Board of Directors or advisory committees; Gilead Sciences: Research Funding; Incyte Corportation: Research Funding.
Carcinocythemia with Microfilaria: Two Diverse Pathologies in One Case
Authors: Samal Swagatika , Mishra Shruti , Mohamedali Rasheeda , Kumar Kishore 
Published: November 2019

Introduction:
Carcinocythemia means circulating tumor cells in peripheral blood. It is a very rare finding I routine practice. The first ever case was reported in 1869 by Ashworth, but it was not till 1976 that the terminology carcinocythemia was coined by Cary et al [1,2]. Only a handful of cases have been reported in literature [3]. We present one such rare case which had an additional finding of micro-filaria in it.
Case Report:
A 60-year-old male patient, hailing from Eastern Ghats of India, presented to the emergency with sudden onset paresis of bilateral lower limbs, hemoptysis, abdominal distention, and urine retention, constipation and persistent chest pain. On evaluation the power of bilateral lower limb was ¼.
He was a known case of Stage IV adenocarcinoma of lungs with bilateral adrenal metastasis. He had received four cycles of PEM + Carboplatin followed by 3 cycles of Carboplatin and Paclitaxel. Last dose of chemotherapy was administered fifteen days prior to presentation.
The patient was not responding to chemotherapy.
He was receiving blood transfusion.
The peripheral smear of the patient revealed circulating tumor cells along with micro-filaria. Cell block was prepared from the sample but unfortunately did not reveal much for special staining. The species of filaria was that of Wuchereria bankrofti. Interestingly, the patient lacked eosinophilia. The total count was 11,000/cumm; Hemoglobin: 8.2gm/dl and Platelet count was 2,10,000/cumm. The counter had flagged for atypical lymphocytes.
The patient deteriorated fast and expired within few hours of presentation. Thus, further evaluation was not possible.
Conclusion:
Carcinocythemia is a rare phenomenon but as a hemato-pathologist vigilance is mandated while evaluating peripheral blood smears to detect such extra-ordinary findings.
References:
1. Ashworth T. A case of cancer in which cells similar to those in the tumors were seen in the blood after death. Aust Med J. 1869;14:146-149.
2. Carey RW, Taft PD, Bennett JM, et al. Carcinocythemia (carcinoma cell leukemia). An acute leukemia-like picture due to metastatic car- cinoma cells. Am J Med. 1976;60(2):273-278.
3. Ronen S., Kroft S.H.,Olteanu H., Hosking P.R.,Harrington A.M.Carcinocythemia: A rare entity becoming more common? A 3-year, single institution series of seven cases and literature review. Int J Lab Hematol. 2019;41:69-79.
Figure

Disclosures
No relevant conflicts of interest to declare.
Near Universal Underestimation of the Risk of Recurrent Venous Thromboembolism (VTE)- an Institutional Survey of Thrombophilia
Authors: Pawar Tushar , Cuker Adam , Garrahy Ian , Donato Anthony , Stevenson Amber , Forman Daniel 
Published: November 2019

Introduction: Current guidelines suggest consideration of indefinite anticoagulation for patients with unprovoked proximal deep vein thrombosis (DVT) and pulmonary embolism at low to intermediate risk for bleeding. In clinical practice, many patients are not treated with prolonged anticoagulation placing them at an increased risk for recurrent VTE. An underappreciation of the risk of recurrent thrombosis may result in the premature discontinuation of anticoagulation in some high-risk patients.
Methods: An online, anonymous questionnaire was sent to all physicians and advanced practice providers in a 711-bed academic community hospital inquiring about their practice, specialty, medical degree, years in practice, and basic questions regarding their comfort and frequency of prescribing anticoagulants. The questionnaire also asked the providers how they would manage ten various clinical scenarios related to anticoagulation management. The participants were graded and scores were calculated based upon percent correct. One question asked the clinicians to estimate the five-year risk of recurrent thrombosis off anticoagulation in a 70-year-old male after completing one year of therapeutic anticoagulation for an unprovoked proximal DVT. The choices given ranged from 1% to 30%. Data was de-identified, SPSS was used to perform t-test and descriptive analysis.
Results: Only 63 (15%) out of 420 respondents appreciated that there is approximately a 30% risk for recurrent VTE after stopping anticoagulation. A slight majority felt that the risk was 5% or less (55.9%). Approximately one-third (29.1%) estimated the risk to be 15%. In the context of practice setting, 22 (37%) from 109 (27%) in-patient providers answered the question correctly, compared to 11 (18%) from 97 (24%) of out-patient providers. In terms of experience, providers with an experience of >10 years (30, 50% correct from 162, 40% responses) did better compared to providers with <10 years of experience (30, 50% correct form 242, 60% responses). t-test results show that providers who answered correctly (30% recurrence), have significant better scores (mean 70.50), compared to those who answered it wrong (mean 57.01), with p-value<0.001.
Conclusion: Underestimation of the risk of recurrent VTE was pervasive in a large, academic healthcare system. It seems likely that this knowledge gap exists outside our institution, and it very likely contributes to premature termination of anticoagulation in some high-risk patients. Quality improvement efforts are needed to educate providers about VTE recurrence risk.

Disclosures
No relevant conflicts of interest to declare.