bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genes Identified in a Hemopoietic Lineage Switch Influence Transcription.
Authors: Winteringham Louise N. , Endersby Raelene , Majewski Ian J. , Beaumont Jennifer , Kobelke Simon , Lalonde Jean-Philippe , Klinken Svend Peter 
Published: October 2019

Abstract
The J2E erythroblastoid cell line responds to erythropoietin (Epo) by morphological maturation and hemoglobin synthesis. However, on rare occasions, these cells have undergone a spontaneous lineage switch and display features of monoblastoid cells which do not respond to Epo. Amongst the genes up-regulated in the monoblastoid variants were Hemopoietic lineage switch (Hls) 5 and 7. Hls5 is a recently identified member of the RING finger, B Box, Coiled coil (RBCC) or tripartite motif (TRIM) family, which includes PML, a gene involved in acute promyelocytic leukaemia. Hls7 is the murine orthologue of Myeloid leukaemia factor 1 (Mlf1), a gene involved in a t(3;5), associated with acute myeloid leukaemia. We have shown previously that Hls7/Mlf1 imposes a dramatic phenotypic change upon the erythroid cells, rendering them monoblastoid (Williams, J. et al EMBO 1999). We have studied the role of Hls5 and Mlf1 in erythroid commitment and differentiation. Ectopic expression of Hls5 inhibits globin production in erythroid cells and suppresses development of B-FUE and C-FUE. A yeast-two-hybrid screen identified FOG-1 as a binding partner of Hls5. Significantly, FOG-1 is a transcriptional co-regulator of GATA-1, which controls globin gene expression. While Hls5 is able to enhance the repression of GATA-1 activity imposed by FOG-1, it is also able to repress GATA-1 transcriptional activity in the absence of FOG-1. Using electrophoretic mobility shift assay we have shown that Hls5 is able to reduce GATA-1 binding to DNA in a dose dependant manner. This observation that Hls5 reduces GATA-1 binding to promoter elements is mirrored by chromatin immunoprecipitation assays. Expression of MLF1 is highest in CD34+ cells, but is markedly down regulated during erythroid differentiation. Microarray analysis identified a number of known transcriptional regulators differentially expressed in the presence of Mlf1 including ets1, Myc intron binding protein and Tbr2. Mlf1 is able to bind DNA and luciferase reporter assays demonstrated that Mlf1 is able to affect transcription. In addition, Mlf1 interacts with a novel member of the hnRNP family viz Mlf1 associated nuclear protein (Manp). Manp binds to DNA, is able to influence the subcellular localisation of Mlf1 by translocating Mlf1 from the cytoplasm to the nucleus. Importantly, Manp also has an affect on transcription. These data demonstrate that both Hls5 and Mlf1 affect transcription of genes associated with erythroid differentiation.
Expression of Endothelial Protein C Receptor Confines Hematopoietic Stem Cell in Murine Fetal Liver.
Authors: Iwasaki Hiroko , Arai Fumio , Kubota Yoshiaki , Suda Toshio 
Published: October 2019

Abstract
Endothelial protein C receptor (EPCR or CD201) is expressed in the endothelial cells of large blood vessels, such as aorta, and contributes to the natural anticoagulant and anti-inflammatory system by activating protein C. Recent study showed that EPCR is also expressed in murine bone marrow, and that the majority of the EPCR-positive cells are the hematopoietic stem cells (HSC) in quiescent state, defined as the side population (sp) fraction in flow cytometry, suggesting the possibility of EPCR involvement in the hematopoiesis. In the murine mid-embryonic stage, on the other hand, the main location of hematopoiesis is fetal liver (FL), where the HSCs are highly proliferative. In this period of development, there are no quiescent HSCs, which is different from adult bone marrow. It is not clarified whether EPCR has any relevance to the fetal hematopoiesis. Here, we demonstrate that EPCR is involved in the hematopoiesis in FL. Immunostaining of murine FL (E12) clearly showed the EPCR-positive cells, and they were located adjacent or connected to the Lyve-1-positive sinusoidal endothelial cells. Some of those were endothelial-like, and others were in round shape, co-expressing c-Kit. In the HSC-enriched Lineage−Sca-1+c-Kit+ (LSK) fraction, the proportion of the EPCR-positive cells was approximately 30%. Sorted EPCR+/LSK and EPCR−/LSK cells were examined for the capability of bone marrow reconstitution and multilineage differentiation. In colony assay, the EPCR+/LSK cells exhibited higher proliferation and differentiation capability into the full range of the hematopoietic cells, including the megakaryocytes and erythroids, while most of the EPCR−/LSK-derived colonies were granulocytes and macrophages. Furthermore, the EPCR+/LSK and EPCR−/LSK cells isolated from donor FL were transplanted with the bone marrow-derived competitor cells into the lethally irradiated recipient mice, resulting in the striking difference between two fractions, i.e., robust long-term reconstitution of EPCR+/LSK cells and almost no reconstitution of EPCR−/LSK cells. The EPCR+/LSK cells were serially transplantable. These data collectively conclude that EPCR-expressing cells in LSK fraction of E12.5 FL exclusively exhibit the capability for long-term bone marrow reconstitution and self-renewal, as well as multilineage differentiation. Thus, the EPCR+/LSK fraction is the highly HSC-enriched population. The function of the endothelial molecule in HSCs will be discussed.
The Vent-Like Homeobox Gene VENTX2 Is Expressed in Human Hematopoietic Progenitor Cells and Promotes Human Myeloid Development In Vitro and In Vivo.
Authors: Arseni Natalia , Ahmed Farid , Rawat Vijay P.S. , Sadlon Timothy J. , Hiddemann Wolfgang , Buske Christian , Feuring-Buske Michaela 
Published: October 2019

Abstract
Recent data indicate that a variety of regulatory molecules active in early development may also play a role in the maintenance of hematopoietic stem cells with repopulating activity. Since it was shown, that the Xvent-2 homeobox gene is part of the BMP-4 signalling pathway in Xenopus, we sought to define the expression profile and function of the human homologue VENTX2 in hematopoietic development. When VENTX2 expression was assessed by TaqMan qRT-PCR in highly purified human cord blood subpopulations, expression of VENTX2 was detected in CD33 and CD15 positive myeloid cells as well as in B and T cells. In addition VENTX2 expression was observed in the primitive CD34+38- human subset as well as in 34+38+ compartment. Furthermore, VENTX2 expression was recurrently detected in bone marrow samples from AML patients at diagnosis as determined by TaqMan qRT-PCR (n=3). In an attempt to characterize the functional relevance of VENTX2 expression for hematopoietic development we retrovirally engineered murine hematopoietic progenitor cells to constitutively express the gene using a MSCV-based retroviral construct with an IRES-EGFP cassette. Successfully transduced cells were injected into lethally irradiated mice or used for in vitro experiments. At the level of the clonogenic progenitor VENTX2 induced myeloid and blocked erythroid differentiation with a significant 1.5 fold increase in the number of CFU-G (n=10; p<0.01) compared to the GFP control and a 5.4 fold decrease in the number of erythroid colonies (n=10; p<0.005) without a change of the total number of colonies produced indicating that VENTX2 promoted granulocytic differentiation in vitro. Re-plating assays showed an over 2 fold increase in the number of secondary CFU-G. In MS-5 murine assay VENTX2 transduced cord blood cells increase CD15+ cells 10.4 fold compared to the control (n=3)(p<0,01). When the effect of VENTX2 was determined on the frequency of LTC-IC by limiting dilution assay (n=2), no major differences were detected between the homeobox gene and the control arm. In NOD/SCID mice VENTX2 induced a 2.9 fold increase in the proportion of CD15+ mature myeloid cells as compared to the GFP control (VENTX2 mean 4 x 106 + 1 x 106 n=7; GFP mean 2x106 cells + 6 x 105 n=9; p<0.02). Using competitive repopulation unit assay (CRU) in NOD/SCID mice we could demonstrate that VENTX2 is able to increase the frequency of CRU cells by 1.8 over GFP control (n=4). These findings characterize VENTX2 as a novel regulatory protein of early human hematopoiesis and extend our knowledge on the regulatory role of non-clustered homeobox genes in hematopoietic development.
Phase II Study of Oral Fludarabine (FAMP) in Combination with Rituximab in Indolent B-Cell Non-Hodgkin Lymphoma (B-NHL)
Authors: Ishizawa Kenichi , Tobinai Kensei , Ogura Michinori , Itoh Kuniaki , Morishima Yasuo , Ando Kiyoshi , Yamamoto Joji , Watanabe Takashi , Uchida Toshiki , Nakata Masanobu , Hayashi Masaki , Hotta Tomomitsu 
Published: October 2019

Abstract
Background and objectives: Although intravenous (IV) FAMP in combination with Rituximab was reported to be effective against indolent B-NHL (JCO2005; 23:694), IV administration of FAMP for 3 to 5 consecutive days is inconvenient in an outpatient setting. We conducted a multicenter phase 2 study to evaluate the efficacy and safety of oral FAMP with Rituximab for relapsed or refractory indolent B-NHL. Patients and treatment: Eligible patients were: aged 20 to 74 years, with indolent B-NHL, with measurable lesions (the greatest transverse diameter > 1.5 cm by CT), performance status 0 or 1, with no major organ dysfunctions. Mantle cell lymphoma was excluded. Prior chemotherapies were limited to < = 2 regimens, and prior rituximab treatments up to 16 times were allowed. Patients who received nucleoside analogs or stem cell transplant were excluded. Patients who had progressive disease within 6 months of receiving rituximab therapy were also excluded. Based on the results of the preceding phase 2 study (JCO2006; 24:174), oral FAMP 40 mg/m2 was administered on day 1 to 5, with rituximab 375 mg/m2 on day 1, repeated every 4 weeks, for up to 6 cycles.
Results: Forty-one patients were enrolled and received oral FAMP with rituximab. Thirty-eight patients (93%) were follicular lymphoma, two with MALT lymphoma, and one with small lymphocytic lymphoma. Thirty-four patients (83%) received rituximab with or without chemotherapy prior to enrollment. Median treatment cycles were 6 cycles (range: 2 to 6, 66% of patients completed 6 cycles of treatment). Investigator-assessed overall response rate and complete response rate were 83% (34/41; CI: 68 to 93%) and 76% (31/41; CI: 60 to 83%), respectively. Central evaluation is pending. With median follow-up period of 9 months, median progression-free survival was not reached, and 28 patients (68%) were still alive without disease progression. Toxicity was primary hematologic, transient and manageable. Most common grade 4 hematologic toxicities included lymphopenia (98%), neutropenia (66%), and leukopenia (42%). Grade 3 or greater non-hematologic toxicities were observed in 29% of patients including one each of grade 4 stomatitis and hyperuricemia. Dose reduction of oral FAMP (from 40 to 30 mg/m2) was necessary in 44% of patients at some points of treatment courses. One patient died from Pneumocystis jiroveci pneumonia and other 2 from disease progression after the end of the study.
Conclusion: Oral FAMP combined with rituximab is highly effective with acceptable toxicities for patients with relapsed or refractory indolent B-NHL who have been mostly pretreated with rituximab, and more convenient than the combination with IV FAMP. Prolonged prophylactic therapy against Pneumocystis jiroveci pneumonia would be recommended.
Pre-Treatment p27 and Bcl-6 Staining Levels Correlate with Response to Bortezomib in Non-Hodgkin Lymphoma: Results from a Tissue Microarray Analysis
Authors: Gerecitano John , Gounder Sivaraman , Feldstein Julie , Ogilvie Shahiba , Lin Dorothy , Zheng Junting , Zhang Zhigang , McDonald Alice , Mulligan George , O’Connor Owen A. 
Published: October 2019

Abstract
Background: Proteasome inhibitors (PI) affect a variety of intracellular processes, including the cell cycle, NF-kB and other signal transduction pathways, and the balance of bcl-2-related proteins, yet it remains unknown which of these targets are most crucial in determining response to PI treatment in non-Hodgkin Lymphoma (NHL). Responses to bortezomib (btz) have been seen in different NHL subtypes in several phase 2 studies. The consistency of response suggests that there may be biological characteristics that determine individual tumor responses to PIs. We used tissue microarray (TMA) technology to determine if pre-treatment tumor characteristics can predict outcome of btz treatment in NHL.
Methods: TMAs were constructed using paraffin-embedded blocks of pre-treatment tissue from patients enrolled in a phase 2, CTEP-NCI sponsored trial of btz in NHL. Microsections were stained for 18 proteins with reported relevance to proteasome function and/or lymphoma prognosis. All stains were evaluated and scored by a central pathologist. Staining was correlated with quality and duration of response (DOR) or time to treatment failure (TTF). The best response was treated as a binary outcome (PR/CR vs SD/POD). Correlation between each marker and response was assessed by univariate analysis. The exact Wilcoxon rank-sum test was used to compare DOR and TTF with respect to the binary marker scores.
Results: This analysis includes 35 of 75 patients treated with btz between 11/6/01 and 2/23/07 for whom pre-treatment tissue blocks could be obtained. Response data were available for 32 of these patients. Diagnoses include: FL (N=10), SLL (N=4), MCL (N=14) and MZL (N=4). Expression of the cell-cycle inhibitor p27 was more common in responding vs non-responding pts (p=0.024), and was also significantly associated with longer DOR (p=0.020) and longer TTF (p=0.021; figure). Presence of Bcl-6 was significantly associated with shorter DOR (p=0.049) and shorter TTF (p=0.048; figure), but not response.
Conclusions: Using TMA analysis, we have shown that NHL patients with pre-treatment p27 staining were more likely to respond to btz, and had a longer DOR and TTF than those without baseline staining. Conversely, patients with baseline Bcl-6 expression had a shorter DOR and TTF than those without. Although the number of patients in this analysis is small, the data will help us generate hypotheses about disease and treatment biology that can be tested in larger studies. We are currently collecting samples from a broader pool of patients treated with btz at MSKCC to verify these results. TTF with bortezomib by (A) p27 and (B) Bcl-6 status.
Figure. Figure.
Human B Cell Lines and Primary B Cells Actively Secrete Granzyme B in Response to IL-2 Family Cytokines.
Authors: Jahrsdoerfer Bernd , Blackwell Sue E. , Simmet Thomas , Weiner George J. 
Published: October 2019

Abstract
It is widely believed that the main function of B cells is antibody secretion, but not cellular cytotoxicity. Recently we found that human B cells activated with interleukin 21 (IL-21) and antibodies to the B cell receptor (BCR) or immunostimulatory oligonucleotides (CpG ODN) develop a phenotype similar to that of cytotoxic T lymphocytes. B cells treated in such a way start to secrete large amounts of granzyme B (GrB) instead of antibodies and, as in the case of B-chronic lymphocytic leukemia (B-CLL), acquire the capability to induce apoptosis in bystander B-CLL cells in a GrB-dependent manner. Using FACS and ELISpot analyses we could now demonstrate that GrB is actively secreted by B cells in a time-dependent manner and that IL-21 is not the only cytokine that induces GrB in B cells. Also cytokine combinations such as IL-10 and IL-4 as well as IL-10 and IFN-alpha induce GrB in normal B cells and various B cell lines including MEC-1 (CLL), ARH-77 (plasma cell leukemia) and Namalwa (Burkitts lymphoma). We conclude that IL-21 and further cytokines can induce B cells to produce functional granzyme B. Further studies are required to elucidate the interactions with B lymphocytes of cells producing these cytokines such as CD4+ T cells, regulatory T cells, NKT cells and plasmacytoid dendritic cells. Our unexpected findings could have significant implications on our understanding of the role of B cells in immune regulation and for a variety of immune phenomena including auto-, cancer and infectious immunity.
Profound Shut-Down of Antigen Specific T-Cell Effector Functions by Dasatinib.
Authors: Weichsel Ralf , Dix Carolin , Wooldrige Linda , Clement Matthew , Fenton-May Angharad , Zezula Josef , Greiner Elisabeth , Gostick Emma , Price David A. , Einsele Hermann , Seggewiss Ruth 
Published: October 2019

Abstract
Dasatinib (Sprycel®, Bristol-Myers Squibb) is a dual BCR-ABL/SRC kinase inhibitor. In 2006, it was approved for the treatment of imatinib-refractory/-resistant CML and Ph+ ALL. An increased infection rate has been described in patients undergoing dasatinib treatment; we postulated that this might be due to inhibition of the SRC kinases LCK and FYN, which play an important role in T cell signalling following antigen recognition. We evaluated dasatinib’s immunobiological effects on purified human CD3+ T cells from healthy blood donors using the promiscuous tyrosine kinase inhibitor staurosporine as a comparator; we also used antigen-specific T cell clones to dissect early T cell signaling events. All assays were performed at clinically relevant doses of dasatinib (1–100nM). In CFSE dilution assays, a dose-dependent inhibition of T cell proliferation was detected with dasatinib (IC50=11nM) and staurosporine (IC50=5nM). These effects of dasatinib, but not staurosporine, were reversible; thus, T cells that were pre-incubated with dasatinib for 24h and then washed, proliferated as well as untreated T cells in the absence of dasatinib. Furthermore, we observed significant inhibition of OKT3-induced up-regulation of the activation marker CD69 (dasatinib IC50=11nM, staurosporine IC50=5nM) and reduced IL-2 production (IC50=2nM, measured by ELISA, for both dasatinib and staurosporine) in purified T cells treated with dasatinib and staurosporine. CD4+ T cells were more sensitive than CD8+ T cells to the inhibitory effects of dasatinib on activation and proliferation (activation IC50=10nM for CD4+ and 15nM for CD8+ T cells; proliferation IC50=10nM for CD4+ and 13nM for CD8+ T cells) while no differences in sensitivity were observed for staurosporine (IC50=4–5 for activation and proliferation in both CD4+ and CD8+ T cells). Since CD8+ T cell-mediated immunity is essential for long-term control of persistent DNA viruses, we evaluated dasatinib’s impact on antigen-specific alpha/beta CD8+ T cell populations specific for CMV and EBV. Profound inhibition of proliferation, cytokine secretion and degranulation was observed in all cases; these observations potentially explain the increased frequency of viral infections in dasatinib-treated patients beyond the induction of myelosuppression. Of note, gamma/delta T cell functions were also inhibited by dasatinib. Dasatinib resulted in significant upregulation of TCR/CD8 at the T cell surface of EBV specific T cell clones indicating that the drug blocks TCR downregulation and recycling at the T cell surface and therefore exerts its effects by blockade of proximal signalling pathways. Overall, these findings provide a rationale to explore the potential of dasatinib as an immunosuppressant in the settings of transplantation and T cell driven autoimmune diseases.
A Randomized Study of Daily Versus Weekly Administration of 2-Chlorodeoxyadenosine in Patients with Hairy Cell Leukemia.
Authors: Zenhausern Reinhard , Leupin Nicolas , Schmitz Shu-Fang Hsu , Solenthaler Max , Tichelli Andre , Heim Dominik , Hess Urs , Leoncini Leda , Bargetzi Mario , Tobler Andreas 
Published: October 2019

Abstract
Background: In hairy cell leukemia (HCL), one cycle of 2-chlorodeoxyadenosine (CDA) is considered a standard treatment. The treatment often results in a high frequency of severe neutropenia and neutropenic fever. Weekly administration of CDA has been reported as effective as daily administration, but with a reduction of febrile episodes and infectious complications. This trial compares the two regimens for efficacy and toxicity.
Design and Methods: HCL patients (pts) were randomized to receive either the standard schedule CDA 0.14 mg/kg/day as a s.c. bolus injection on days 1–5 (Arm A) or the experimental schedule of one weekly dose of CDA 0.14 kg/day as a s.c. bolus injection on five consecutive weeks (Arm B). The primary endpoint was the average of 6 weekly white blood cell count after randomization, analyzed using ANCONA to adjust for baseline count. 100 pts were required to detect a difference between 0.8 G/L and 1.2 G/L with 5% type I errror and 80% power. Secondary endpoints were response rates, other acute hematotoxicity, acute infection rate and fever within 10 weeks, remission duration (RD), event-free survival (EFS) and overall survival. Clinical and laboratory examinations were repeated weekly during the first 6 weeks, then biweekly up to week 10, every 3 months up to 2 years and every 6 months thereafter. Response was assessed at week 10, then every 6 months up to 2 years, and every year thereafter.
Results: 50 pts were enrolled to each arm. There was no significant difference between treatment arms (A vs. B) in the primary endpoint (2.2 G/L vs. 3.0 G/L), the rate of grade 3/4 leucocytopenia (94% vs. 84%) or neutropenia (90% vs. 80%), acute infection of any grade (44% vs. 40%), fever (44% vs. 38%), hospitalization (38% vs. 34%), and blood transfusion (22% vs. 30%). Response rate (CR + PR) at week 10 was 78% with 95% confidence interval (CI) (64%, 88%) vs. 68% with CI (54%, 80%) (1-sided p-value 0.13). Over all follow-up visits the best response rate was improved to 86% in both arms. The median follow-up time was 50.2 months vs. 42.3 months. The median values for RD and EFS have not been reached, and the between-arm differences were not significant. One pt in each arm died during treatment and one additional pt in arm A died during follow-up.
Conclusions: Weekly application of CDA fails to show any advantage in toxicity or efficacy compared to standard approach.