bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tumor Evasion of the Immune System: Inhibiting p38 MAP Kinase Signaling Restores the Function of Dendritic Cells.
Authors: Yi Qing , Wang Siqing , Yang Jing , Wang Jianfei , Wezeman Michele , Kwak Larry W. 
Published: April 2020

Abstract
Dendritic cells (DCs) from cancer patients are functionally defective, however, molecular mechanisms underlying are still poorly understood. In this study, we used the murine 5TGM1 myeloma model to examine the effect and mechanism of tumor-derived factors on the differentiation and function of DCs. Myeloma cells (5TGM1) or tumor culture conditioning medium (TCCM) were shown to inhibit differentiation and function of BM-derived DCs (BMDCs), evidenced by the downregulated expression of DC-related surface molecules, decreased IL-12 but increased IL-10 secretion, and compromised capacity of the cells to activate allospecific T cells in vitro. Similar results were obtained with other murine myeloma cells MOPC-315 and MPC-11. Moreover, TCCM-treated BMDCs were inferior to normal BMDCs at priming tumor-specific humoral and cellular immune responses in vivo (in the 5TGM1 mouse model). Neutralizing antibodies against IL-6, IL-10, and TGF-β partially abrogated the effects. TCCM treatment activated p38 mitogen-activated protein kinase (MAPK) and JNK but inhibited extracellular signal-related kinase (ERK). Inhibiting p38 MAPK by three different specific inhibitors was found to restore the phenotype, cytokine secretion, and function of TCCM-treated BMDCs. Vaccinating mice with BMDCs obtained from cultures in which both TCCM and p38 inhibitor were added was as efficacious as normal BMDCs at inducing tumor-specific antibody, type-1 (IFN-γ) T-cell, and CTL responses. Thus, our results suggest that tumor-induced p38 MAPK activation and ERK inhibition in DCs may be a new mechanism for tumor evasion, and regulating these signaling pathways in vivo or during DC differentiation may provide new strategies for generating potent DC vaccines for immunotherapy of multiple myeloma and other tumors.
Decitabine Low-Dose Schedule (100 mg/m2/Course) in Myelodysplastic Syndrome (MDS). Comparison of 3 Different Dose Schedules.
Authors: Kantarjian Hagop , O’Brien Susan , Giles Francis , Ravandi-Kashani Farhad , Faderl Stefan , Garcia-Manero Guillermo , Davis Jan , Issa Jean-Pierre 
Published: April 2020

Abstract
Background Decitabine (DAC), a hypomethylating agent, has shown activity in MDS. DAC 150 mg/m2 by continuous infusion has been associated with CR rates of 10% to 20%. We investigated optimizing the dose schedule of DAC in MDS.
Study Group and Methods Patients (pts) with IPSS intermediate 1–2 & high risk MDS were randomized to one of 3 schedules of DAC: 1) 20 mg/m2 IV over 1 hour daily x 5; 2) 10 mg/m2 IV over 1 hour daily x 10; or 3)10 mg/m2 subcutaneously (SQ) BID x 5. A total of 95 pts are to be treated; Bayesian randomization is implemented based on CR rates. Courses were given every 28 days. Delays to allow counts recovery were permitted every 3 courses, or if myelosuppression without disease, or severe myelosuppression complications. Pts were allowed to receive erythropoietin 40,000 units weekly for anemia, or GCSF if needed. Response criteria for CR & PR were as for AML (PR requiring also ↓ blasts by &gt;50%). Clinical benefit (CB) referred to one or more of: platelets î by ≥ 50% and &gt;30 x 109/L, or granulocytes increase by ≥ 100% and to &gt;109/L, or hemoglobin î by ≥ 2 g/dl or transfusion independence, or splenomegaly ↓ by 50% or more, or monocytes ↓ by 50% or more (pretreatment &gt;5 x 109/L).
Results 92 pts have been treated; median age 65 (31–90) yrs; 66% &gt;60 yrs old. IPSS: intermediate-1 25%; intermediate-2 38%; high 19%; CMML 17% Cytogenetic abnormalities 57%; secondary MDS 17%; marrow blasts &gt; 10% in 31%. 27 pts had prior erythropoietin; 17 had prior GCSF; 22 had other prior therapies. Presently, 89 pts have received 1 course. Results: 32 CR (36%); 7 PR (8%); 13 marrow CR + CB (15%); 16 CB (18%); overall response 68/89=76%. Median courses to CR 3 (range 1 to 6). Median follow-up of 9 months; 48 pts continue on DAC. Compared with a 114 pts with MDS who received intensive chemotherapy (2000–2004), CR rate was lower with DAC (36% vs. 45%), overall response rate was favorable; 6-week mortality was lower with DAC (1% vs. 21%); and estimated survival favorable (p = 0.00007). CR rates by schedule: 5 days IV 24/58 (41%); 5 days SQ 4/14 (28%); 10 day IV 4/17 (24%). There was more myelosuppression with 10 day IV. After 55 patients were randomized, the 5 day IV arm was determined statistically superior, therefore, remaining patients were not randomized, but were treated with 5 days IV therapy.
Conclusions DAC has significant anti-MDS activity; 2) optimal schedule: 20 mg/m2 IV over 1 hour daily x 5; 3) timely repeated courses needed for optimal response.
High Circulating CD34 Cells, Dacrocytes, Clonal Hematopoiesis, and JAK 2 Mutation Differentiate Secondary Myelofibrosis Associated with Pulmonary Hypertension from Myelofibrosis with Myeloid Metaplasia.
Authors: Popat Uday , Liu Enli , Guan Yongli , Prchal Josef T. 
Published: April 2020

Abstract
Myelofibrosis with myeloid metaplasia (MMM) is a clonal myeloproliferative disorder, characterized by splenomegaly and myelofibrosis. Like all myeloproliferative disorders, it is due to an acquired somatic mutation of a hematopoietic progenitor resulting in clonal erythrocytes, platelets, and granulocytes. A single acquired point mutation of JAK2 1849G&gt;T (V617F), a tyrosine kinase with a key role in signal transduction from growth factor receptors, occurs in 50%–97% of patients with MMM, essential thrombocythemia (ET) and polycythemia vera (PV). We studied 25 myelofibrosis patients with myeloid metaplasia and myelofibrosis complicating PV or ET. These were compared to 19 patients with secondary myelofibrosis of equivalent severity associated with pulmonary hypertension (PH) treated by epoprostenol. In these two groups we compared peripheral blood CD34 counts, clonality of granulocytes and platelets in peripheral blood, mutational status of JAK 2 kinase gene, and morphology of peripheral blood and bone marrow. Heterozygosity for JAK 2 1849G&gt;T somatic mutation was seen in 17 of 23 (74%) patients with MMM including 10 of 15 patients (67%) with idiopathic myelofibrosis and 7 of 8 patients (88%) with myelofibrosis complicating PV or ET, but was absent in all 19 patients with myelofibrosis associated with PH (P&lt;0.0001, Fisher exact test 2 tailed). The number of peripheral blood CD 34 cells was significantly higher in patients with MMM compared to patients with secondary myelofibrosis associated with PH; 1.1% (95% CI, 0.58%–1.64%) in patients with MMM versus 0.08% (95% CI, 0.04%–0.12%) in patients with PH, or 0.05% (95% CI, 0.03%–0.06%) in normal healthy controls (P&lt;0.01). Further, patients with PH lacked dacrocytes, erythroid precursors, or myeloid precursors (leukoerythroblastic picture) on examination of the blood smear. Clonal hematopoiesis was found only in those women with marrow fibrosis due to MMM, PV and ET and not in patients with secondary marrow fibrosis (P &lt; 0.0001).
We conclude that a high circulating CD34 count, clonal platelets and granulocytes, presence of dacrocytes, and JAK2 1849G&gt;T (V617F) mutation of clonal progenitors are the intrinsic features present in patients with myelofibrosis due to myeloproliferative disorders and that these features are not due to the abnormal marrow architecture that is seen in secondary myelofibrosis.
Analysis of JAK2V617F Mutation, PRV-1 Overexpression and Endogenous Erythroid Colony (EEC) Formation Show Different Coexpression Patterns among Ph-Negative Chronic Myeloproliferative Disorders.
Authors: Bellosillo Beatriz , Besses Carles , Florensa Lourdes , Longaron Raquel , Navarro Gemma , Gimeno Eva , Sole Francesc , Vila Rosa M. , Serrano Sergi 
Published: April 2020

Abstract
Introduction. Recently, the JAK2V617F mutation has been reported in the majority of PV patients as well as in a variable percentage of ET and IMF patients. Some authors have reported a high correlation of JAK2 mutation with PRV-1 overexpression and the formation of EECs. In the current study we have analyzed the pattern of positivity of these three biomarkers in a cohort of Ph-negative MPD patients.
Patients and methods. 103 Ph-negative MPD patients (58 ET, 37 PV and 8 IMF) from a single institution were studied. Patients were diagnosed according to the PVSG and Barosi criteria. EEC formation was determined at diagnosis. At the time when PRV-1 and JAK2 mutation were analyzed 29/103 patients were receiving platelet-lowering therapy ± ASA, 26/103 patients only received ASA and 48/103 received no specific treatment. PRV-1 expression was quantified by real-time reverse transcriptase (RT)-PCR in RNA from granulocytes. Analysis of JAK2V617F was performed by direct sequencing using granulocyte RNA. Results. JAK2 mutation was observed in 21/58 ET (36.2%), 30/37 PV (81.1%) and 5/8 IMF (62.5%). PRV-1 was overexpressed in 25/58 ET (43.1%), 35/37 PV (94.6%) and 6/8 IMF (75%) and EECs formation was seen in 31/58 ET (53.4%), 34/37 PV (91.9%) and 6/8 IMF (75%).
All markers were simultaneously positive (group A) in 43/103 patients (41.7%), concurrently negative (group B) in 25/103 patients (24.3%) and both positive and negative markers (group C) were observed in 35/103 patients (34%). In group A, 65% were PV patients, 26% were ET patients and 9 % were IMF patients. In group B, 8% were PV patients, 84% were ET patients and 8 % were IMF patients. In group C, 20% were PV patients, 74% were ET patients and 6 % were IMF patients.
Regarding diagnosis, 76% of PV and 50% of IMF patients belonged to group A, whereas the majority of ET patients (45%) pertained to group C (table). When comparing ET and PV, a significant difference was observed (p&lt;0.001) concerning group distribution.
Conclusion. These results show that, although a good correlation has been observed for the simultaneous expression of these three biomarkers, differences in the pattern of positivity, specially in ET, indicate that not all Ph-negative patients share the same pathogenetic mechanisms and point to other coexisting genetic abnormalities.
Diagnosis ET PV IMF All markers positive (group A) 11 (19%) 28 (76%) 4 (50%) All markers negative (group B) 21 (36%) 2 (5%) 2 (25%) Positive and negative markers 26 (45%) 7 (19%) 2 (25%) Total 58 37 8
Inactivation of the PRDM1/BLIMP1 Gene in Non-GC-Type Diffuse Large B-Cell Lymphoma.
Authors: Pasqualucci Laura , Compagno Mara , Houldsworth Jane , Monti Stefano , Grunn Adina , Shipp Margaret A. , Dalla-Favera Riccardo 
Published: April 2020

Abstract
PRDI-BF1/Blimp1 is a zinc finger transcriptional repressor expressed in post-germinal center (GC) B cells and required for terminal B cell differentiation.
The PRDM1/BLIMP 1 locus lies on chromosomal band 6q21–q22.1, a region frequently deleted in B-cell non-Hodgkin’s lymphomas suggesting the existence of one or more tumor suppressor loci (Gaidano et al, Blood80:1781, 1992). To test whether genetic alterations affecting the BLIMP1 gene may be involved in DLBCL pathogenesis, we performed PCR amplification and direct sequencing of the BLIMP1 coding sequences in 136 cases, including 20 cell lines and 116 primary biopsies. Gene expression profiling analysis using the Affymetrix Gene Chip system was used in 93 cases to classify them as germinal center B-cell like (GCB, N=38), activated B-cell like (ABC, N=35) and type III (N=20). Nonsense mutations were found in 7 of 136 cases. Four of these mutations generated premature stop codons, predicting severely truncated proteins of 61 to 244 aminoacids; in three cases, a single bp substitution affecting the exon 2 splice donor site led to insertion of 101 nucleotides from intron 3 and a premature stop codon. One primary tumor case carried a mutation within the intron 3 splice acceptor site, and one cell line displayed a gene rearrangement in one allele with deletion of the second allele. Strikingly, 6 of the 7 nonsense mutations identified segregated with the ABC phenotype (the remaining case was not profiled), suggesting that these alterations may be common and specific in this subtype of DLBCL (6/35, 17%). In addition, missense mutations generating aminoacid substitutions were found in 8 additional cases, and complete lack of Blimp-1 protein expression was found in most ABC-type DLBCL cases. These observations suggest that inactivation of the BLIMP1 gene may occur also by other mechanisms, including the generation of dominant negative mutants, chromosomal deletion or epigenetic silencing, in a large fraction of DLBCL. Functional studies are currently being performed to corroborate these data. Overall, these results suggest that BLIMP1 may act as a tumor suppressor gene, whose loss or inactivation may contribute to lymphomagenesis by blocking post-GC differentiation of B cells toward plasma cells.
Defining Candidate Oncogenes Leading to Increased Susceptibility to Leukemia in eed Mutant Mice.
Authors: Sauvageau Martin , Sauvageau Guy 
Published: April 2020

Abstract
We previously showed that loss of function of the chromatin regulator polycomb group gene (PcG) eed increases susceptibility to lymphoid tumour development (Sauvageau, M. et al. Blood 104 (11); 213). The human eed locus is in a region of chromosome 11 (11q14.2–22.3) which is associated with recurrent deletions in several reported cases of lymphoproliferative diseases. The persistant expression of the wild-type allele of eed is maintained in lymphomas developing in eed+/− animals. This suggests a haploinsufficient function for this gene in preventing tumorigenesis. We recently exploited an insertional mutagenesis screen to identify new cooperative leukemia-inducing genes in eed mutant mice. 325 retroviral insertion sites (RIS) representing 189 different gene loci have been identified by inverse-PCR from a total of 51 lymphomas (25 eed−/− and 26 wild-type). This screen revealed 18 gene loci known to be cancer related and 21 new common insertion sites (CIS) such as sh2d3c (n=4 tumours), fgfr3 (n=15 tumours) and myo5b (n=7 tumours). More than 97% of these CIS were common to both eed mutant and wild-type animals. We next assessed the expression levels of all the genes found in a 100 Kb region of genomic DNA surrounding the CIS identified in our screen in eed mutant and wild-type tumours as well as in the corresponding non-leukemic tissues. Almost 17% of the 48 genes analyzed, including fgfr2, fgfr3, ttc16 and adam15, are aberrantly expressed in non-transformed eed mutant cells when compared to wild-type controls (levels 5–100+ fold). Importantly, several of these genes are either aberrantly expressed in wild-type and eed mutant tumours or represent true CIS thus indicating their possible contribution to early tumour development in eed mutant mice. Moreover, our results do not incriminate eed as a modifier of gene expression once cells are fully transformed, since the oncogenic complement is similar in eed mutant and wild-type leukemias. Collectively, our results link the haploinsufficient role of eed to the appropriate regulation of genes involved in leukemia development.
Fine and Ultrafine Particles Differentially Affect the PFA-100-Times and Raise Proinflammatory Cytokines in Human Blood.
Authors: Forestier Marc , Buechi Linda , Hermann Corinna , Hartung Thomas , Beer Juerg H. 
Published: April 2020

Abstract
INTRODUCTION: Peaks of ambient air pollution with increased concentrations of particulate matter (i.e. PM2.5: Fine particles of &lt; 2.5 μm diameter and UFP: Ultrafine particles of &lt;0.1 μm diameter) easily reach levels of 100’000 particles/cm3 and are associated with increased cardiovascular morbidity and mortality. Especially the UFP-fraction rapidly crosses cellular membranes by non-phagocytotic mechanisms and is translocated into the circulation. The absorbed microparticles may affect the coagulation directly or indirectly via monocyte/macrophage activation. The data on prothrombotic and inflammatory effects are controversial, depending on the type, size and charge of particles and the experimental models chosen.
HYPOTHESIS: We therefore hypothesized that typically sized particles differentially affect human platelets and coagulation either directly or indirectly by the proinflammatory response.
METHODS AND RESULTS: Three microparticle sources were mixed with citrated human blood at concentrations of 5 and 50 μg/ml for one hour:
a) PM2.5 polystyrene beads (PS) of 0.66 μm diameter. b) UFP ultrafine carbon black (ufCB, 14 nm, Printex), and c) residual oil fly ash (ROFA, with contents of Al, Zu, Cu-ions, and residual polyaromatic hydrocarbons).
We calculated that &gt;800 μg of microparticles may be absorbed by the human lung daily and thus a dose of appr. 5 μg/ml blood could be achieved easily.
Platelet aggregation with ADP, collagen, arachidonate and ristocetin at different concentrations was not affected by any of the three types of microparticles and neither was PT, aPTT, fibrinogen, DDimer or soluble P-selectin. Direct microscopical observation did not show platelet aggregates, nor rosetting of platelets with leucocytes, nor mixed platelet aggregates with microparticles. PFA-100 CADP, however, was prolonged in the presence of PS beads from 85 ± 3 sec to 101 ± 6 (n = 3, p &lt; 0.04); ROFA, on the other hand, shortened it by more than 20 sec to 78 ± 2 vs 110 ± 6 sec (n = 3, p &lt; 0.05) and ufCB/UFP did not affect it. The standardized endogenous thrombin potential as measured by the thrombinoscope did not exhibit significant changes under the conditions chosen.
Preliminary data of a highly standardized assay of cytokine release after 24 hours of stimulation with low dose LPS (1μg/ml blood) indicates a 2 - 3 fold increase of interferon, interleukine-1 and TNFa, but not of interleukine-8.
CONCLUSION: Our data demonstrate a direct shortening effect on shear induced platelet aggregation (PFA-100) by ROFA and a prolongation by positively charged PS beads. None of the three particle types showed a direct effect in any of the other coagulation assays evaluated. The strong proinflammatory cytokine response to all three microparticle preparations is likely responsible for the procoagulant / prothrombotic effects which have been observed in experimental mouse and hamster models.
Inactivation of p38 MAPK Extends Self-Renewal Capacity of Haematopoietic Stem Cells.
Authors: Ito Keisuke , Hirao Atsushi , Arai Fumio , Matsuoka Sahoko , Takubo Keiyo , Ikeda Yasuo , Suda Toshio 
Published: April 2020

Abstract
Haematopoietic stem cells (HSCs) undergo self-renewing cell divisions and maintain blood production for their lifetime. Appropriate control of HSC self-renewal is critical for maintenance of haematopoietic homeostasis. Here we show that activation of p38 MAPK limits lifespan of HSCs in response to increasing levels of reactive oxygen species (ROS) in vivo. Although normal quiescent HSCs maintain a low level of oxidative stress, an increase in ROS was observed in HSCs after transplantation as well as in aged mice. In vitro treatment with BSO (Buthionine sulfoximine), which depletes intra-cellular glutathion, increased ROS (H2O2) level in immature hematopoietic cell population, c-kit+Sca1+Lin- (KSL) cells, in a dose-dependent manner. Low dose concentration of BSO suppressed reconstitution capacity of HSCs, whereas higher concentration did not affect progenitors. These data indicate that HSCs are much more sensitive to increased ROS than progenitors and are consistent with our previous results from Atm−/− mice in which ROS level is elevated in vivo. Here we focused on MAPKs for the stem cell dysfunction since it has been shown that several MAPKs are activated in response to ROS. We evaluated effects of MAPK inhibitors for p38, JNK or ERK in incubation of KSL cell with BSO. p38 inhibitor (SB203580), neither JNK nor ERK inhibitor, restored reconstitution capacity of HSCs after transplantation, suggesting that activation of p38 may contributes to defect of stem cell function in vivo. To address the question, we evaluated p38 activation in Atm−/− BM cells by immunohistochemistry. Surprisingly, p38 protein was phosphorylated only in KSL cells, but not other more differentiated cell populations, despite that the ROS levels were comparable among the cell population of mice. In response to activation of p38, p16INK4a was up-regulated only in KSL cells. The data indicates a possibility that stem cell-specific p38 activation negatively regulates self-renewal of HSCs. We then investigated a role of p38 activation on self-renewal of HSCs in vivo. When p38 inhibitor was intraperitoneally administered both before and after BMT, the level of repopulation achieved was comparable to that of the wild-type. Furthermore, Atm−/− mice that received long-term p38 inhibitor treatment did not show either anemia, a decrease in progenitor colony-forming capacity, or reduced frequencies of stem cell subsets. These data demonstrate that the activation of p38 present in HSCs promotes the exhaustion of stem cell pool in response to elevation of ROS. It has been proposed that aging is driven in part by a gradual depletion of stem cell functional capacity. There are evidences that inappropriate production of oxidants is connected to aging and life span. We propose a possibility that p38 activation in response to ROS plays a critical role for limit of stem cell capacity.
Activation of the Classical Pathway of Complement by Resting and Shear Stress-Stimulated Human Endothelial Cells.
Authors: Yin Wei , Weksler Babette , Varon David , Savion Naphtali , Ghebrehiwet Berhane , Peerschke Ellinor 
Published: April 2020

Abstract
Complement activation is associated with a variety of inflammatory conditions including atherosclerosis, but the mechanism of complement activation in these settings is poorly understood. Endothelial cells (EC) play an important role in vascular pathology and express a variety of complement receptors, including gC1qR/p33, recognizing the globular domain of the complement component C1q. In preliminary studies, purified recombinant gC1qR/p33 was found to support C1q-dependent C4 activation in vitro, comprising 19.5% ± 8.3% (mean ± S.D., n=5) of that produced by aggregated IgG. In contrast, a truncated form of gC1qR/p33, lacking the C1q binding domain, failed to support C4 activation. Additional studies were performed with immortalized bone marrow microvascular EC to investigate classical complement pathway activation and deposition. EC were exposed to anticoagulated (0.32 % sodium citrate) human plasma, diluted (1/10) in 0.01 M HEPES buffered modified Tyrode’s solution, pH 7.5, containing 2 mM Mg Cl2 and 1 mM CaCl2, for 60 min, 37°C. A solid phase ELISA approach was used to detect EC-associated C1q and C4 activation (C4d). Statistically significant deposition of C4d (0.72 ± 0.3. OD units (ODU), n=4)(p=0.04) and C1q (0.57 ± 0.19. ODU, n=4) (p=0.002) was observed on EC that had been immobilized on poly-L-lysine coated microtiter wells. Consistent with classical complement pathway activation, C4d deposition remained at baseline (0.23 ± 0.13, ODU, n=4) in the presence of 10 mM EDTA, but C1q deposition was unaffected. Moreover, no significant C1q or C4d deposition occurred when endothelial cells were exposed to C1q depleted serum. Similar studies were performed using EC grown to confluence on Type I collagen to examine the effect of shear stress (12 dynes/cm2 for 1 hour in a cone-and-plate shearing device), simulating flow conditions in coronary arteries, on classical complement pathway activation and deposition. Compared to static conditions, shear stress resulted in an approximately 50% increase in C1q and C4d deposition on EC. This was accompanied by an approximately 2-fold increase in EC binding of a monoclonal antibody, 60.11, recognizing the N-terminal C1q binding domain of gC1qR/p33. Taken together, these data present evidence for a potential paradigm shift, illustrating immune complex independent classical complement pathway activation by gC1qR/p33, and deposition of activated classical complement components on EC. The generation and deposition of active complement components on EC is likely to contribute directly to vascular inflammation and atherosclerotic changes.