bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Existing Limited Sampling Models for Therapeutic Drug Monitoring of Busulphan in Children and Adults Undergoing SCT.
Authors: Hassan Zuzana , Sandström Marie , Hassan Moustapha 
Published: April 2020

Abstract
Busulphan (Bu) is used in high dose conditioning regimen prior to stem cell transplantation. Bu has a narrow therapeutic window and over- and under-dosing may have a fatal outcome. Bu pharmacokinetics and pharmacodynamics were extensively studied and wide inter- and intra-individual variation was found. Several limited sampling models (LSM) have been developed for Bu administered orally to simplify therapeutic drug monitoring and consequently dose adjustment. The aim of this study was to evaluate the existing LSM in adults and children undergoing conditioning regimen before SCT. Seventy-four patients (62 adults and 12 children) with malignant and non-malignant diseases were analysed. Plasma was sampled at 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5 and 6 hours after the first dose of Bu. Bu was determined using gas chromatography with electron capture detection. The area under the plasma concentration-time curve (AUC) for time interval 0 to 6 hours was determined using Winnonlin program and trapezoidal rule. Results were compared to the estimated AUCs using LSMs (Vassal 1992, Schuler 1994, Hassan 1996, Chatergoon 1997). The best correlation between the AUCs determined using trapezoidal rule and 3-points model by Schuler was found (R²=0.95 for all patients, R²=0.97 for children and R²=0.94 for adults). In children, a correlation between AUCs determined with trapezoidal rule and following LSMs was found: 2-points LSM by Schuler (R²=0.94), LSM by Hassan (R²=0.94), LSM by Vassal (R²=0.81) and 3 of 5 LSMs by Chatergoon (R²=0.85, 0.88 and 0.87, resp.). AUCs in children determined using Winnonlin showed good correlation with both Schuler’s models, model by Hassan and one of 4-points models by Chatergoon. However, the correlation between the AUCs determined using trapezoidal rule and Winnonlin was good in children (R²=0.98), but not in adults (R²=0.65). Thus, several limited sampling models are suitable for AUC estimation in children, while there is only one suitable model for adults. This conclusion is made with reservation that even the trapezoidal rule may underestimate the real AUC dependent on sampling density.
High Expression of Multidrug Resistance-Associated Proteins Predicts Prognosis in Acute Lymphoblastic Leukemia in Children and Adults.
Authors: Plasschaert Sabine L.A. , de Bont Eveline S.J.M. , Boezen Marike , van der Kolk Dorina M. , Daenen Simon M.J.G. , Faber Klaas Nico , Kamps Willem A. , de Vries Elisabeth G.E. , Vellenga Edo 
Published: April 2020

Abstract
Background: Patients with acute lymphoblastic leukemia (ALL) are treated with different chemotherapeutic drugs, which can be transported by ABC-transporters, including six multidrug resistance-associated proteins (MRPs). New insights suggest that a drug resistance profile, in which multiple transporters act in concert, is more likely to predict prognosis than one single transporter. The aim of this study was to investigate the expression profile of MRP1-6 in ALL in both children and adults and determine its impact on prognosis.
Methods: mRNA expression of MRP1-6 was analyzed by real-time PCR in human de novo ALL samples from 56 children and 49 adults. Of these patients, 32 showed a T-lineage and 73 a B-lineage immunophenotype.
Results: Adults showed a significantly higher expression of MRP1 (median value 1.08 vs. 0.69), MRP2 (0.96 vs. 0.53) and MRP3 (0.31 vs. 0.07) than children. However, no difference in expression levels was observed between children and adults who developed a relapse. High expression of one MRP in individual patients was correlated with increased expression of multiple MRPs. The ability to discriminate between patients who will remain in continuous complete remission and patients who will relapse was determined by receiver operating characteristic (ROC) curves. When children and adults were analyzed together, the area under the ROC curves showed that MRP1 (AUC 0.72, p=0.002), MRP2 (AUC 0.71, p=0.002), MRP3 (AUC 0.72, p=0.001), MRP5 (AUC=0.70, p=0.004) and MRP6 (AUC=0.68, p=0.009) predicted relapse. Using median values as cutoff for high versus low expression, high expression of all six MRP genes, except MRP4, was significantly associated with reduced event-free survival in children and adults (Kaplan-Meier curves with Log-rank tests).
Conclusion: Our results suggest that a profile with high mRNA expression of MRP1, MRP2, MRP3, MRP5 and MRP6 is involved in drug resistance in ALL. This unfavorable profile is more often observed in adults, and is associated with reduced event-free survival.
Expression of the Human ATP-Binding Cassette Transporter Superfamily in Acute Myeloid Leukemia.
Authors: Ho Maria , Hogge Donna E. , Ling Victor 
Published: April 2020

Abstract
Members of the ATP-Binding-Cassette (ABC) transporter superfamily of proteins are involved in resistance to multiple chemotherapeutic drugs ( Multidrug Resistance or MDR) in a variety of malignant cells including leukemic blasts. Overexpression of some ABC transporters has been demonstrated in acute myeloid leukemia (AML) and is associated with clinical MDR and failure of conventional chemotherapy, which occurs frequently in this leukemia. Recent studies have also demonstrated ABC transporter expression in primitive normal hematopoietic cells, including progenitors which may give rise to AML after malignant transformation. In this study we used quantitative Real-Time PCR to assess and compare the expression level of all 47 known human ABC transporters in AML blasts and normal peripheral blood. Peripheral blood blasts from 17 patients with newly-diagnosed AML who subsequently received conventional remission induction therapy with cytosine arabinoside and daunorubicin were studied; 11 of these subsequently achieved complete remission of their leukemia while the remaining 6 had chemotherapy refractory disease. Contrary to expectations, no consistent difference in mRNA levels was found between the chemotherapy responsive and refractory groups of patient samples for any ABC transporter, including known MDR-related members such as MDR-1 and BCRP. Profiling of the 47 ABC transporters in 12 normal peripheral blood samples (6 mobilized with G-CSF, 6 non-mobilized) showed that TAP1 and MRP3 were 3.3-fold (P = 0.032) and 24-fold (P = 0.012), respectively, higher in normal donors as compared to AML patients. ABCA7, ABCB8, MRP3, MRP7, ALDP, PMP70 and PMP69 were greater than 3-fold higher (P &lt; 0.05) in G-CSF-mobilized as compared to steady state normal blood. These results suggest that levels of ABC transporter mRNA expression in AML blasts prior to chemotherapy are not predictive of treatment response. This raises questions regarding the role of ABC transporters in intrinsic as opposed to induced or acquired chemotherapy drug resistance, which in turn has important implications in clinical usage of ABC-reversal agents. In addition, we identified expression of a variety of ABC transporters in both AML blasts and normal blood cells suggesting that this class of transporter proteins may have importance in both normal and malignant hematopoiesis.
Glucosylceramide Synthetase Inhibitors Sensitise B-CLL Cells to Cytotoxic Agents without Reversing P-gp Functional Activity.
Authors: Gerrard Gareth , Butters Terry D. , Mehta Atul B. , Hoffbrand A. Victor , Hughes Derryln , Burgess Michael , Ganeshaguru Kanagasabai 
Published: April 2020

Abstract
Malignant B-cells from a high proportion of chronic lymphocytic leukaemia (B-CLL) patients over express the multidrug resistance (MDR) -1 gene encoded transmembrane efflux pump P-glycoprotein (P-gp). Inhibition of glucosylceramide synthesis has been shown to correlate with the expression and function of P-gp and sensitise cells to cytotoxic agents. We analysed the ability of glucosylceramide synthetase (GCS) inhibitors N-butyl-deoxygalactonojirimycin (OGB-1, 500μM) and N-nonyl-deoxygalactonojirimycin (OGB-2, 100μM) to sensitise B-CLL cells to conventional cytotoxic drugs 2-chlorodeoxyadenosine (CdA), chlorambucil (Chl) and fludarabine (FdR) using the in vitro cytotoxicity MTT assay. The effect on P-gp activity was also analysed using the calcein-AM accumulation assay and the results expressed as multidrug activity factor (MAF), where a MAF of &gt;10 in the presence of a P-gp inhibitor denotes P-gp functional activity. GCS inhibitors were cultured with B-CLL cells for 24-48h before the assays were performed. The P-gp negative cell line CEM-CCRF had no MAF activity with an IC50 for vincristine (a known P-gp substrate) of &lt;1ng/ml. The P-gp over expressing cell line CEM-VLB showed a MAF value of 96.4 with zosuquidar trihydrochloride (Z.3HCL), a specific inhibitor of P-gp, 15.7 with OGB-1 and 45.9 with OGB-2. The IC50 for vincristine was reduced from &gt;10ug/ml to 55.5ng/ml in the presence of OGB-2. In peripheral blood mononuclear cells from 3 normal volunteers (all P-gp +ve), the mean MAF value for Z.3HCL was 23.86 and for OGB-2 was 16.2. In 9/13 B-CLL samples there was P-gp functional activity in the presence of Z.3HCL with a mean MAF value of 22.15 (range 11.27–37.3). P-gp was over expressed in10/13 B-CLL samples. However, when available samples from this cohort were assessed with OGB-1 (n=4) and OGB-2 (n=13) the MAF value was &lt;10. Nevertheless, sensitisation of B-CLL cells was observed by a reduction in the IC50 in the presence of OGB-1 with CdA in 3/4 (to 40% in the presence of cytotoxic drug alone), Chl in 3/4 (39%), FdR in 2/4 (26%) and in the presence of OGB-2 with CdA in 8/13 (42%), Chl in 5/13 (40%) and FdR in 7/13 (34%). Although GCS inhibitors sensitize B-CLL cells to cytotoxic drugs in some B-CLL patients, they do not appear to have any effect on P-gp functional activity.
Alpha-1 Antitrypsin Is a Potent Inhibitor of Cytokine-Induced Hematopoietic Stem Cell Mobilization.
Authors: van Pel Melissa , van Os Ronald , Velders Gerjo A. , Hagoort Henny , Lindley Ivan J. , Willemze Roelof , Fibbe Willem E. 
Published: April 2020

Abstract
Previously, we have shown that IL-8 and G-CSF-induced hematopoietic stem cell (HSC) mobilization is inhibited in mice that underwent low dose (0.5 Gy) total body irradiation (TBI), whereas the number of progenitor cells in the bone marrow remained similar in all groups. The mechanism underlying this inhibition remains unknown. Since the release of granular proteases by neutrophils is well known to play a role in HSC mobilization, we also considered a possible role for serine protease inhibitors in the induction of HSC mobilization. Serine proteases, such as elastase and cathepsin G, are irreversibly inhibited by serine protease inhibitors including alpha-1 antitrypsin (alpha-1 AT) and alpha2-macroglobulin. In-vitro tests revealed that addition of bone marrow extracellular extracts, that were obtained from murine femurs 24 hours following low dose (0.5 Gy) TBI, inhibited the activity of exogenous elastase in a chromogenic substrate conversion assay up to 78.1 % compared to extracts obtained from sham irradiated controls (p&lt;0.05). Since elastase inhibition by alpha2-macroglobulin cannot be detected in a chromogenic substrate conversion assay, alpha-1 AT was considered as the primary candidate serine protease inhibitor to inhibit elastase activity in our in-vitro system. Quantitative PCR of total bone marrow cells revealed that alpha-1 AT mRNA was 20-fold increased relative to the housekeeping gene ß-actin and 7-fold relative to the housekeeping genes HPRT and GAPDH at 24 hours following low dose (0.5 Gy) TBI. In addition, Western blot analysis indicated that alpha-1 AT protein concentrations were significantly (p&lt;0.01) increased in bone marrow extracellular extracts derived from low dose (0.5 Gy) irradiated mice, compared to extracts obtained from sham-irradiated controls (5.1 ± 0.6 scanning units [SU] vs. 3.9 ± 0.7 SU for 0.5 Gy;n=8 vs. 0 Gy; n=6 respectively). To further substantiate a possible in-vivo role of alpha-1 AT in the inhibition of HSC mobilization, we administered alpha-1 AT (300 μg/mouse i.p.) at 2 hours and at 5 minutes prior to IL-8 injection (30 μg/mouse i.p.). Administration of alpha-1 AT prior to IL-8 injection completely (p&lt;0.05) inhibited IL-8-induced HSC mobilization (472.9 ± 289.5 CFU-GM per ml blood for IL-8; n=5 vs. 44.8 ± 35.5 CFU-GM per ml blood for alpha-1 AT/IL-8; n =11). These results indicate that 1) alpha-1 AT is a potent inhibitor of IL-8-induced HSC mobilization and 2) in-vivo induced alpha-1 AT contributes to the inhibition of HSC mobilization after low-dose (0.5 Gy) TBI. We hypothesize that a critical balance between serine proteases and serine protease inhibitors plays an important role in cytokine-induced HSC mobilization.
Intrathymic and Extrathymic Notch-Dependent T Lineage Checkpoints during Normal Development and after Bone Marrow Transplantation.
Authors: Maillard Ivan , Sambandan Arivazhagan , Zediak Valerie P. , Schwarz Benjamin , Xu Lanwei , Aster Jon C. , Pear Warren S. , Bhandoola Avinash 
Published: April 2020

Abstract
The essential role of Notch for T lineage commitment is well established, but it remains unclear where and on which progenitor subset(s) Notch signals act. Addressing these questions is critical to understand the regulation of lymphopoiesis in normal and lymphopenic settings, such as after bone marrow transplantation (BMT).
In normal mice, a small number of progenitors settle in the thymus from the blood and expand to generate a pool of early T lineage progenitors (ETPs). At the population level, ETPs can give rise to T cells, NK cells, B cells, DCs and myeloid cells. We found that ETPs could be subdivided based on expression of the cytokine receptor Flt3, which is expressed on about 10% of ETPs and is inversely correlated with expression of Notch target genes. B lineage potential was restricted to ETPFlt3 positive cells. The Notch targets Hes-1, Hes-5, and Deltex1 were present at low levels in ETPFlt3 positive and high levels in ETPFlt3 negative cells. Induction of Notch signaling resulted in the rapid downregulation of surface Flt3 expression. In contrast, culture of ETPFlt3 negative cells in the absence of Notch ligands resulted in upregulation of Flt3. Although both ETP subsets were efficient T lineage progenitors, ETPFlt3 negative cells had a more rapid differentiation kinetics resembling DN2 thymocytes, consistent with a more advanced state of T lineage commitment relative to the Flt3 positive subset. In mice reconstituted with HSCs transduced with the pan-Notch inhibitor DNMAML1 (Maillard et al., Blood 2004), no ETPFlt3 negative and very few ETPFlt3 positive cells were observed, indicating that the generation of ETPs is Notch-dependent. These observations position the physiological Notch checkpoint either very early after thymic seeding and/or in a prethymic location.To further investigate if Notch-dependent prethymic T lineage commitment occurs in adult mice, we studied lymphoid reconstitution early after BMT. ETPs were absent in the thymus of recipients until ≥ 6 weeks post-BMT, despite the presence of donor-derived pre-T cells and double positive thymocytes as early as 2–3 weeks post-BMT. Instead, cells with pre-T cell characteristics were present in the spleen of BMT recipients in the first month post-BMT. These cells were absent when DNMAML1-transduced bone marrow was used as the source of HSCs, indicating that generation of extrathymic pre-T cells is Notch-dependent. Thus, extrathymic sites may be important for efficient lymphoid reconstitution after BMT. Altogether, our results indicate that both intrathymic and extrathymic Notch-dependent checkpoints regulate T lineage commitment during normal development and in the post-BMT setting.
Erythroid-Specific Intergenic Transcripts Originate from the 200 Kb Region 5′ to the LCR in Erythroleukemia and Human Primary Cells.
Authors: Xiang Ping , Fang Xiangdong , Yin Wenxuan , Stamatoyannopoulos George , Li Qiliang 
Published: April 2020

Abstract
Intergenic transcripts have been discovered in globin and other multigene clusters. The role of this transcription activity in gene regulation is still unclear. We found aberrant globin gene transcripts that initiated from the regions 77 kb and 236 kb 5′ to the e gene in K562 and primary cells. The most abundant splicing form of the transcripts is a 500–600 bp RT-PCR product containing 36 bp RNA from the −240 kb region spliced to the upstream region starting at −270 bp of the e gene promoter. Several spliced transcripts also contain RNA fragments from the −77 kb region, or from the −12 kb region (between HS3 and HS2 of the LCR), or from the −8 kb region (between HS2 and HS1). A total of 17 different transcripts were found in K562 cells. Transient transfection assays showed that the −77 kb and −236 kb regions had promoter activity in K562 cells. DNase I hypersensitive sites were detected in these two regions in K562 cells, but not in Jurkat cells. The −236 promoter activity is located within the region encompassing a retrotransposon and the −77 region is located at 2 kb 5′ to an olfactory receptor gene. To test whether such aberrant transcripts occur in primary cells, we tested various human tissues. In fetal bone marrow (72 days) a spliced transcript was detected by RT-PCR and confirmed by DNA sequencing, which contained a 36 bp RNA from the −236 kb region and was spliced to the e gene promoter starting at −270 bp. Using a RNA RACE technique, we also found several aberrant globin gene transcripts in human placenta, adult bone marrow, and fetal liver (20–40 weeks, BD Biosciences). These transcripts contained 181 bp RNA from the −76 to −77 kb region 5′ and the sequence starting at −214 bp 5′ to the cap site of the e gene. While it is unclear whether these transepts or transcription itself has any biological function, this erythroid-specific transcription occurring in the 200 kb region 5′ to the LCR may play a yet-unknown role in globin gene regulation.
Hydroxamic Acids Derivatives Induce γ Globin Gene Expression in Vivo.
Authors: Cao Hua , Jung Manfred , Stamatoyannopoulos George 
Published: April 2020

Abstract
We have previously shown that four hydroxamic acids: butyric and propionic hydroxamic acids, subericbishydroxamic acid (SBHA) and suberoylanilide hydroxamic acid (SAHA) are potent inhibitors of histone deacetylase and strong inducers of fetal hemoglobin expression in vitro (Exp Hematol.31:197, 2003). In the present study we tested their effect on fetal hemoglobin synthesis in vivo. Transgenic mice carrying the human μLCR Aγ construct continue to express the human γ gene in the adult stage of development ( γ/α mRNA ratio ~ 5%, Blood.77:1326, 1991). These mice were crossed to mice heterozygous for a thalassemia gene due to β globin gene deletion (PNAS.92:11608, 1995). The β thalassemia/μLCR Aγ mice represent an appropriate moderately anemic animal model for testing the effects of Hb F inducers. Compounds were administered subcutaneously with a mini-osmotic pump continuously for 7days in a high and a low concentration. Concentrations were: for butyric hydroxamic acid: 500mg/kg/day/100mg/kg/day; for propionic hydroxamic acid: 500mg/kg/day/100mg/kg/day; for SAHA: 100mg/kg/day/20mg/kg/day; and for SBHA: 200mg/kg/day/40mg/kg/day. Two test groups were studied. In group 1, 70μL mice blood was drawn every other day up to 20 days; in group 2, 70μL mice blood was drawn only on days 0 and 21. Reticulocytes and F reticulocytes were measured using flow cytometry, while γ globin gene expression was quantitated by RNase protection assay. Butyric and propionate hydroxamic acids increased reticulocytes by 70.52% (from 13.96% to 23.81%) and 172.52% (from 10.34% to 28.20%) respectively. There was only small increase in reticulocytes in the mice treated with SAHA (from 13.33% to 15.36%), SBHA (from 14.24% to 16.27%) and the PBS control (11.06% to 14.11%). All the compounds increased the level of γ mRNA: butyric hydroxamate by 53.07%; propionic hydroxamate by 40.05%; SAHA by 49.87%, and SBHA by 34.05%. These results suggest first that all the hydroxamic acid derivatives we used increase fetal hemoglobin in vivo in the thalassemia animal model; second butyric and propionic hydroxanic acids are in addition inducers of in vivo erythropoiesis.
Naive and Non Naive CD4+ and CD8+ T Cell Subsets Distribution in Blood and Marrow Grafts and Their Impact on Patients’ Outcome after Allogeneic Stem Cell Transplantation.
Authors: Yakoub-Agha Ibrahim , Saule Pasquine , Grutzmacher Claudine , Cracco Pascale , Magro Leo , Bauters Francis , Villard Florence , Depil Stephane , Jouet Jean-Pierre , Dessaint Jean Paul , Labalette Myriam 
Published: April 2020

Abstract
Peripheral G-CSF-mobilized blood stem cells (PBSC), use as alternative to marrow stem cells (MSC), is associated with enhanced engraftment and accelerated hematopoietic recovery after allo-SCT. However, despite an increased number of donor T cells infused, the incidence of acute GVHD with PBSC appears to remain identical or less than with MSC. Recent works on the heterogeneity of the human CD4+ and CD8+ T cells have individualized 4 subsets: namely, naive (CCR7+CD45RA+), central memory (TCM, CCR7+CD45RA−), effector memory (TEM, CCR7−CD45RA−), and CD45RA+ effector memory cells (TEMRA, CCR7−CD45RA+). To our knowledge, the T cell subsets proportions in MSC and PBCSP grafts remain unknown. The impact of the infused T cell subsets on patients’ outcome is still to be investigated. Between September 2003 and July 2004, 25 consecutive hematopoietic allo-SCT (12 MSC and 13 PBSC) were considered for this study. Multiple combinations of immunophenotyping analysis were used to prospectively examine immune parameters related to graft as well as to early reconstitution. Early post-transplant complications including acute GVHD, relapse and infections were assessed. As expected, T cells subsets, B cells and NK cells numbers were significantly higher in PBSC grafts (versus MSC). However, proportions of CD4+ and CD8+ T-cell subsets were comparable in the 2 types of graft and similar to normal values observed with peripheral blood of healthy adults. Table below summarize the distribution of T cell subsets within T CD4+ and T CD8+ in the two types of graft. The incidence of acute GVHD was significantly higher in pts receiving &gt; 5% of CD8+ TEM cells among infused CD8+ cells (p&lt;0.05) suggesting a detrimental role of this CD8+ subset. Pts who developed acute GVHD, compared to those who did not, had a faster expansion of CD4+ and CD8+ TEM cells (p&lt;0.003), and CD8+ TEMRA cells (p&lt;0.05) after transplantation. Conclusion: this report contributes to the establishment of reference values regarding the distribution of T cell subsets within PBSC and MSC graft. Although, the quantity of infused T cell does not seem to influence early complications after allo-SCT, the qualitative composition of graft regarding T cell subsets, appears to be of great importance in acute GVHD occurrence.
MSC PBSC CD4+ naive 45% 48% CD4+ TCM 25% 24% CD4+ TEM 20% 16% CD4+ TEMRA 5% 2% CD8+ naive 40% 50% CD8+ TCM 4% 7% CD8+ TEM 23% 14% CD8+ TEMRA 29% 22%