bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Population Pharmacokinetic Model Describing the Activity-Time-Course of PEG-Asparaginase in Children.
Authors: Hempel Georg , Lanvers-Kaminsky Claudia , Mueller Hans-Joachim , Wuerthwein Gudrun , Boos Joachim 
Published: October 2019

Abstract
PEG-Asparaginase is an important part of many treatment protocols for ALL. In many centres Asparaginase activity is measured after administration of PEG-asparaginase. However, a predictive pharmacokinetic model is lacking. Such a model would be helpful for dose adjustment and decision making when to switch to another preparation due to the development of inactivating antibodies. Previously described models like linear one-compartment [V.I. Avramis et al., Blood 2002, 99: 1986–1994] or a one-compartment Michaelis-Menten model [H.J. Mueller et al., Cancer Chemother. Pharmacol. 2002, 49, 149–154] describe the data sufficiently for one dose alone, but cannot account for the phenomenom that the time to reach a lower activity limit after administration is not increasing with increasing the dose. Therefore, we analysed 1189 serum activity measurements in 185 children from the ALL-BFM 95 study. Patients received 500, 1000 or 2500 U/m2 PEG-Asp on up to 9 occasions. Serum asparaginase activity was measured using a semi-automatic enzymatic assay with a limit of quantification of 2 U/l [C. Lanvers et al. Anal. Biochem. 2002, 309, 117–126]. Data analysis was done using nonlinear mixed effects modelling (NONMEM Vers. V). Different models like Michaelis-Menten, linear first-order, Weibull and gamma models were tested. The best model applicable to all dosing groups was a modified first-order one-compartmental model with clearance increasing with time according to the formula: Cl = Cli*exp(0.0853*t) with Cli=initial clearance, and t=time. Addition of a second compartment did not improve the model. A typical activity-time course of a patient receiving 1000 U/m2 is shown below displaying the typical shape observable in all patients and in all doing groups. The population parameters found were: Volume of distribution (V) 1.05 ± 27.3% l/m2, Cli 60.3 ± 70.8% ml/day/m2 (mean ± interindividual variability). Interoccasion variability was substantial with 0.223 l/m2 for V and 37.7 ml/day/m2 for Cl, respectively. A subgroup of one third of the patients is identifiable showing a high clearance probably due to the development of inactivating antibodies. Drug monitoring of serum PEG-Asparaginase activity is required to identify these patients who do not benefit from PEG-Asp therapy. The pharmacokinetic model presented here should help to reduce the number of required serum samples per patient.
Figure Figure
Differential Effects of Delta1 and Jagged1 in Early Human Myelopoiesis: Correlation with Distinct Gene-Expression Profiles in CD34+ Cells.
Authors: Neves Hélia , Weerkamp Floor , Naber Brigitta A.E. , Gameiro Paula , Becker Jörg D. , Lucio Paulo , Clode Nuno , van Dongen Jacques J.M. , Staal Frank J.T. , Parreira Leonor 
Published: October 2019

Abstract
The Notch ligands Delta1 and Jagged1 are known to differentially affect the development of B and T-cell lineages but their function in the myelopoiesis is still unclear. Here we show that Delta1 and Jagged1, expressed by bone-marrow-derived stromal cells, differentially affect de myeloid development of human CD34+ cells: Jagged1 increases their clonogenic potential both at the level of bi- (CFU-GM) and uni-potent progenitors (CFU-G and CFU-M), without quantitatively affecting terminal cell differentiation; Delta1 strikingly reduces the number of CFU-GM and differentiated monocytic cells.
Gene expression profiling of CD34+ cells cultured in contact with Jagged1 or Delta1, reveals that the observed phenotypic/functional differences correlate with the emergence of distinct transcription profiles for genes related to hematopoietic-differentiation programs, receptors for growth-factors and Notch-signalling.
The comparative analysis of different CD34+ sub-populations revealed that: cells with similar phenotypes (CD34+CD7−), but emerging in distinct environments (Delta1 or Jagged1), have different “lineage-specific” transcription profiles, Delta1-CD34+ cells exhibiting an almost “pure” myeloid program, whereas Jagged1-CD34+ cells are enriched in transcripts for B- and myeloid lineages; the same environment (Delta1) originates CD34+ cells with different phenotypes, as to CD7 expression, which differ in their lineage-specific transcription profiles: Delta1-CD34+CD7+ cells show a high expression of T/NK-cell related genes in contrast with their CD7− counterparts which express a myeloid-lineage program. Furthermore, Jagged1 and Delta1-stromas have differential effects in the expression of genes coding for receptors for several hematopoietic growth factors. Overall, these transcription profiles agree with the specific cell-lineage-affiliation of the corresponding CD34+ cell sub-population. Quantitative analysis of transcripts from Notch-signalling-related genes in different CD34+ sub-populations showed that cells with similar phenotypes (CD34+CD7−), but emerging in distinct environments (Delta1 or Jagged1), have different expression profiles of receptors and targets of Notch. In the case of Delta1 environment, we observe a predominance of Notch3 and Hes1 transcripts, whereas Jagged1-CD34+ cells are enriched in Notch1 and Deltex transcripts. In the same stromal environment (Delta1) but different in CD34+ cell sub-populations Notch3 receptor was up-regulated. Delta1, contrary to Jagged1, promotes up-regulation of modulators of Notch signaling.
Together, the data show that Delta1 and Jagged1 modulate gene-expression programs in CD34+ cells in ways that contribute not only to cell-lineage-affiliation but also to the functional interactions between developing cells and their micro-environment.
A Novel NF-kB:NFAT Enhanceosome Synergistically Regulate CD154 Gene in Aggressive B Cell Lymphomas.
Authors: Pham Lan , Tamayo Archito , Yoshimura Linda , Lin-Lee Yen-Chiu , Ford Richard J. 
Published: October 2019

Abstract
Non-Hodgkin’s Lymphoma (NHL) causes many deaths world wide, and is one of the few cancers that have a continual increase in incidence and mortality rates over the last few decades. Diffused large B cell lymphoma (DLBCL) is an aggressive B cell lymphoma that accounts approximately 40% of all NHL-B cells. We have previously shown that dysregulated CD40 ligand (CD40L/CD154) expression in DLBCL maintains lymphoma cell growth and cell survival. CD40 ligand is a member of the TNF superfamily of proteins that has a wide variety effects throughout the immune system and is critical for both cellular and humoral immunity. It was originally thought that CD154 expression was restricted to activated CD4+ T lymphocytes. However, expression of CD154 has also been demonstrated in non-lymphocytic leukocytes such as mast cells, basophils, eosinophils, dendritic cells and macrophages. More importantly, dysregulated CD154 expression has been noted in a number of diseases, including systemic lupus erythematosus (SLE), Alzheimer’s, and in B cell lymphomas. Although the functional analysis of CD154 has been extensive, little is known about the mechanisms controlling CD154 expression in activated T cells, let alone in normal and malignant B cells. In this study, we show that constitutive NF-kB and NFAT activation in aggressive lymphoma B cells directly interact and synergistically regulate CD154 gene expression. Immunoprecipitation and confocal analyses indicate that NFATc1 and NF-kB (p65 and c-rel) complex and colocalize in lymphoma B cells. Chromatin Immunoprecipitation (CHIP) assays analysis demonstrate that NFATc1, p65 and c-rel bind to the CD154 promoter, that is enhanced by HDAC inhibitor (TSA or SAHA) treatments. HDAC inhibitors also enhance CD154 promoter activity, providing evidence that CD154 transcriptional regulation involves histone acetylation. Over-expression studies show a synergistic effect by NFATc1 and NF-kB (c-rel) on the CD154 promoter. Promoter deletion and site direct mutagenesis studies on the CD154 promoter reveal that the transcriptional regulation of CD154 requires two sites, the distal kB site at −1180 and a proximal NFAT site at −250. These sites bind to both, NFAT and NF-kB proteins, as wells as the DNA architectural protein HMG-1, indicating that the CD154 promoter DNA may loop and form an enhanceosome-like complex. Studies using siRNA to p65, c-rel, or NFATc1 repress CD154 promoter activity, indicating that these transcription factors are necessary and sufficient for CD154 gene transcription. These findings strongly suggest a novel control mechanism for CD154 gene transcription, therefore, providing potential treatment modalities for lymphoma B cells as well as other disorders involving dysredulated CD154 expression.
Damaged Murine Brain Induces ES Cells into Migration and Proliferation.
Authors: Srivastava Anand S. , Shenouda Steve , Carrier Ewa 
Published: October 2019

Abstract
An understanding of how ES cells differentiate in vivo into neural cells is essential for developing and refining transplantation strategies for the nervous system, as well as for understanding the molecular mechanism underlying neurogenesis. We hypothesized that damaged neural tissues will create an environmental niche and stimulate ES cells to migration and differentiation into the neural cells. We induced damage in murine (C57BL/6) brain by injecting 2.5 μl of PBS into the left frontal and right caudal regions and confirmed neural damage by immunohistochemistry. Yellow fluorescent protein (EYFP) expressing embryonic stem cells (50,000 cells/1μl) (Nagy et al., Cell Biol., 2001; 115:49–58.) were injected into the non-damaged left caudal portion of the brain. Using histochemistry (anti-GFP peroxidase, cross-reacting with YFP) and fluorescent microscopy, we observed migration of ES cells from the injection site (left caudal) to the damaged site (right caudal and left frontal) at 5 days post injection. The survival of ES cells was demonstrated by the real-time PCR assay of stemness genes such OCT4, SOX2 and FGF4. The portions of the damaged neural tissues containing ES cells demonstrated 4-fold increase in expression of these genes one week of post injection in comparison to non-injected ES cell murine brain suggesting proliferation. Increased PDGF protein expression and histochemistry studies demonstrated that ES cells responded to damaged neural tissues, migrated to the opposite site of the brain and proliferated. Differentiation studies are in progress and will be presented. This work demonstrates the responsiveness of undifferentiated ES cells to the damaged neural tissues and provides a model of in vivo stem cellà stem cell niche interactions.
Ex-Vivo Generation and Expansion of Both Lymphoid and Myeloid Lineages from Human Cord Blood (CB) HSC Using a Serum-Free Human Mesenchymal Stem Cell Based Culture System.
Authors: Frias Ana , Porada Christopher D. , Crapnell Kirsten B. , Cabral Joaquim M.S. , Zanjani Esmail D. , Almeida-Porada Graca 
Published: October 2019

Abstract
The in vitro culture of a hematopoietic stem cell (HSC) graft with either media containing animal-derived components or a feeder layer with ill-defined pathogenic potential such as xenogeneic cell lines or cells modified by viral transformation poses risks that concern scientists and regulatory agencies. In the present studies, we avoided these risks by evaluating the ability of a human stromal-based serum free culture system (hu-ST) to support the ex-vivo expansion/maintenance of human CB HSC. CB CD34+ enriched cells were cultured in serum free medium in the presence of hu-ST with SCF, bFGF, LIF and Flt-3, and the cultures were analyzed for expansion, phenotype and clonogenic ability. We have previously reported the ability of this culture system to allow the successful expansion/maintenance of HSC along the myeloid pathway. In the present study, we investigated whether we could further develop this culture system to simultaneously expand myelopoiesis and lymphopoiesis in vitro. To this end, cord blood CD34+ cells were cultured for a total of 28 days and analyzed every 3 days for expansion and phenotype. There was a progressive increase in CD34 cell number with time in culture. The differentiative profile was primarily shifted towards the myeloid lineage with the presence of CD33, CD15, and CD14. However, a significant number of CD7+ cells were also generated. At week 2 of culture, we observed that 30% of the cells in the culture were CD7 positive. These CD7+CD2-CD3-CD5-CD56-CD16-CD34- cells were then sorted and either plated on top of new irradiated hu-ST layers in the presence of SCF, FLT-3, IL-7, IL-2, and IL-15, or cultured with IL-4, GM-CSF, and FLT-3 in the absence of stroma. Both of these cultures were maintained for an additional 2 weeks. In both sets of cultures, further expansion in the total cell number occurred with the time in culture, and by the end of the week 2, we observed that 25.3±4.18% of the cells had become CD56+ CD3-, a phenotype consistent with that of NK cells. Furthermore, cytotoxicity assays were performed and showed cytotoxic activity that increased in an E:T ratio-dependent fashion. 38.6% of the CD7+ cells grown in the presence of IL-4, GM-CSF, and FLT-3 became CD123+CD11c-, a phenotype characteristic of nonactivated dendritic cells, while 7.3–12.1% adopted an activitated dendritic cell phenotype CD83+CD1a+. In summary, we developed an in vitro culture system that reproducibly allows the effective ex vivo expansion of human cord blood HSCs while maintaining the capability of generating both myeloid and lymphoid hematopoiesis in vitro.
The CALM/AF10 Fusion: Molecular Analysis of the Fusion Transcripts in 13 Cases of AML and ALL; Gene Expression Profiling Reveals HOX Gene Deregulation.
Authors: Krause Alexandre , Kohlmann Alexander , Haferlach Torsten , Schoch Claudia , Schnittger Susanne , Mecucci Cristina , Ludwig Wolfgang D. , Bohlander Stefan K. 
Published: October 2019

Abstract
The t(10;11)(p13;q14) is a recurring translocation associated with the CALM/AF10 fusion gene which is found in undifferentiated leukemia, acute myeloid leukemia, acute lymphoblastic leukemia and malignant lymphoma with poor prognosis. The CALM/AF10 fusion protein was reported to be the most common fusion protein in T-ALL with TCR gamma delta rearrangement. We have analyzed samples from 9 patients with different types of leukemia: case 1 (AML M2), case 2 (AML M0), case 3 (Pre T-ALL), case 4 (Acute Undifferentiated Leukemia), case 5 (PreT-ALL), case 6 and 7 (ProT-ALL), case 8 (T-ALL), case 9 (AML), with a t(10;11) translocation suggesting a CALM/AF10-rearrangement. The samples were analyzed for the presence of the CALM/AF10 and AF10/CALM mRNA by RT-PCR and sequence analysis. All these patients were found positive for the CALM/AF10 fusion.
In addition, we analyzed a series of twenty-nine patients with T-ALL with gamma delta rearrangement. Among these patients, four were positive for CALM/AF10 transcripts, indicating a high incidence of CALM/AF10 fusions in this group of leukemia. We found three different breakpoints in CALM at nucleotide 1926, 2091 and a new exon, with 106 bases inserted after nt 2064 of CALM in patient 4. In AF10 four breakpoints were identified: at nucleotide position 424, 589, 883 and 979. In seven patients it was also possible to amplify the reciprocal AF10/CALM fusion transcript (case 1, 3, 4, 8, 9, 10 and 11). There was no correlation between disease phenotype and breakpoint location. The patients were 5 to 46 years old (median 25). Ten CALM/AF10 positive patients were further analyzed using oligonucleotide microarrays representing 33,000 different genes (U133 set, Affymetrix). Analysis of microarray gene expression signatures of these patients revealed high expression levels of the homeobox gene MEIS1 and the HOXA cluster genes HOXA1, HOXA4, HOXA5, HOXA7, HOXA9, and HOXA10. The overexpression of HOX genes seen in these CALM/AF10 positive leukemias is reminiscent of the pattern seen in leukemias with rearrangements of the MLL gene, and complex aberrant karyotypes suggesting a common effector pathway (i.e. HOX gene deregulation) for these diverse leukemias. It is known that alhambra, the Drosophila homologue of AF10 can act on polycomb group responsive elements, which play a critical role in the regulation of the HOX gene clusters. It is thus conceivable that the CALM/AF10 fusion proteins acts in a dominant negative fashion on wild type AF10 function relieving the repression that is presumably normally exerted by AF10 on the expression of HOX genes.
Towards the In Vivo Identificaton of Leukemogenic Fusion Proteins.
Authors: Chen Ying , Froehlich Nicole , Bohlander Stefan K. 
Published: October 2019

Abstract
Currently there are no methods available to identifiy leukemogenic fusion proteins in vivo. All available methods, like Southern blotting, PCR, FISH or Western blotting, require the destruction of the cells that are assayed. A method for the in vivo detection of leukemogenic fusion proteins would be highly desirable because it would open up new approaches to study leukemia and might lead to novel treatment strategies.
We have developed a strategy for the in vivo detection of the BCR/ABL fusion protein. BCR/ABL is found in virtually all cases chronic myeloid leukemia (CML) and a large proportion of acute lymphoblastic leukemia (ALL). Animal model have shown that the BCR/ABL fusion protein is required for the induction and maintenance of leukemia. The fact that BCR/ABL fusion protein is crucial for the development of leukemia makes this fusion protein an attractive target for therapy development. Our BCR/ABL detection strategy is based on protein-protein interactions and a proof of principle for the strategy was implemented in the yeast system. Two detection proteins are expressed in the cells: 1) protein A, a Gal4-DNA binding domain/BCR interacting protein fusion protein and 2) protein B, a Gal4-activation domain/ABL interacting protein fusion protein. Only when BCR/ABL is present in the cell, do protein A, protein B, and BCR/ABL form a trimeric complex which activates the transcription of reporter genes under the control of Gal4-upstream activating sequence (UAS).
Yeast cells (strain CG1945) transformed with a protein A expressing plasmid (pGBT9-BCR-interactor), a protein B expressing plasmid (pGAD424-ABL1-interactor), and a BCR/ABL expressing plasmid (pES1-BCR/ABL) showed expression of the reporter genes HIS3 and LACZ. The expression of the HIS3 reporter gene was assayed by growth of the yeast cells on medium lacking histidine. The expression of the LACZ gene was verified by a beta-galactosidase filter assay.
Yeast cells that were transformed with the pES1 plasmid without the BCR-ABL coding region did not show activation of the reporter genes. Several other negative controls were also negative. Thus the method was able to clearly distinguish between BCR/ABL expressing cells and cells did not express BCR/ABL.
We are presently adapting this system for use in mammalian cells. The flexibility of our strategy allows us to freely choose the reporter or effector genes. Therapeutically more useful effector genes are suicide genes, which encode pro-drug converting enzymes (e.g. HSV thymidine kinase), or markers that can easily be assayed (e.g. green fluorescent protein).
Cytogenetic Remission Status after Induction Chemotherapy for AML and High-Risk MDS Predicts Long-Term Outcome.
Authors: Balleisen Sebastian , Barbara Hildebrand , Brigitte Royer-Prokora , Andrea Kuendgen , Norbert Gattermann , Ulrich Germing , Rainer Haas 
Published: October 2019

Abstract
Cytogenetic findings at diagnosis have an important impact on prognosis in AML and MDS. Therefore, treatment is commonly stratified according to karyotype. Another important prognostic factor is remission status after induction chemotherapy. However, the diagnosis of remission, and the resulting treatment decisions, are usually not based on cytogenetic findings, but rely on peripheral blood counts and bone marrow blast cell counts. We analysed the prognostic impact of cytogenetic remission status in 115 patients with abnormal karyotype who received induction chemotherapy because of AML (n=102) or MDS (n=13). Initial karyotypes were as follows: 14x t(15;17), 9x t(8;21), 5x inv(16), 55 intermediate-risk, and 32 complex karyotypes. The following induction protocols were used: 38x TAD, 4x HAM, 25x Ida-Ara, 36x ICE, and 3x other protocols. Eleven patients received induction chemotherapy plus ATRA. 23 patients underwent allogeneic transplantation after induction therapy, either as late consolidation in cytologic remission (CR), or as standard treatment in high-risk patients. 78 patients achieved CR, 21 achieved partial remission (PR), and 16 patients were non-responders (NR).
There were 26 patients who reached cytological CR but still showed an abnormal karyotype after induction. 17 of these 26 patients had been classified as standard-risk and therefore did not receive intensified consolidation. In 59 patients, a normal karyotype was found after induction therapy. 24 of 28 patients belonging to low-risk cytogenetics (t15;17, t8/21, or inv16) achieved cytogenetic complete remission (CCR). The CCR rate was much lower in patients with intermediate-risk cytogenetics (24/55) and patients with complex karyotypes (11/32). Median survival in the group achieving CCR was 40 months, as compared to 11 months in patients with persistence of abnormal karyotype after induction (p<0,00005). The difference remained highly significant when calculated only for patients with complex or intermediate-risk karyotypes (median survival 29 vs 11 months).
Conclusions: Cytogenetic analysis after induction chemotherapy is useful to detect residual disease and therefore provides meaningful information in addition to cytology. Achieving cytogenetic remission after induction therapy is strongly correlated with a better long-term outcome. Patients with a persisting abnormal karyotype must be regarded as high-risk patients who should receive intensified treatment.