bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cladribine in Weekly Versus Daily Schedule for Untreated Active Hairy Cell Leukemia: Final Report of Polish Adult Leukemia Group (PALG) Prospective, Randomized, Multicenter Trial.
Authors: Robak Tadeusz , Jamroziak Krzysztof , Gora-Tybor Joanna , Blonski Jerzy Z. , Kasznicki Marek , Dwilewicz-Trojaczek Jadwiga , Dmoszynska Anna , Wojtaszko Maria , Zdziarska Barbara , Calbecka Malgorzata , Hellmann Andrzej , Stella-Holowiecka Beata , Sulek Kazimierz , Skotnicki Aleksander B. , Zawilska Krystyna , Kloczko Janusz , Seferynska Ilona , Konopka Lech , Piszcz Jaroslaw , Ceglarek Berandetta , Lewandowski Krzysztof , Gawronski Krzysztof , Kostyra Aleksandra , Nowak Wieslaw , Wiater Elzbieta , Dybowicz Jacek , Wojtaszko Maria , Molendowicz-Portala Lucyna 
Published: October 2019

Abstract
Cladribine (2-chlorodeoxyadenosine, 2-CdA) has dramatically improved prognosis of hairy cell leukemia (HCL), though the 2-CdA treatment-associated life-threatening infections may shorten potentially long-term survival of HCL patients. In search of optimal mode of 2-CdA administration in HCL, we compared the standard 5-day 2-CdA protocol with a novel weekly 2-CdA schedule that was suggested to be equally effective, but less toxic. Between the 1st January 1998 and the 31st September 2005, 132 patients with previously untreated, active HCL from 14 hematology centers were included to the study. Patients were randomly assigned to receive 2-CdA at 0.12 mg/kg in 2-hour intravenous infusion for 5 days (64 patients), or 2-CdA at 0.12 mg/kg in 2-hour intravenous infusion once a week for 6 weeks (62 patients). The response to chemotherapy was evaluated according to the NCI guidelines and treatment-related toxicity was recorded using standard WHO criteria. One hundred and sixteen patients were included in the final analysis of the trial. Comparison of the treatment response between daily and weekly 2-CdA protocols showed similar complete remission rate (76% and 72%, p=0.86) as well as similar overall response rate (95% and 91%, p=0.41). Survival analysis did not show significant difference between the study arms. Median progression-free survival equaled 4.3 years (95%CI = 3.3 – 5.2) and 5.1 years (95%CI = 4.7 – 5.6) (p=0.28) for patients treated with daily and weekly schedule, respectively. The estimated 6.5 year overall survival was 91% for daily and 88% for weekly 2-CdA protocol, p = 0.40. Interestingly, the analysis of adverse events did not confirm lower toxicity of the weekly 2-CdA schedule. Of special interest, there were no significant differences between daily and weekly protocol in the rate of treatment-related neutropenia (47% vs. 47%, p=0.97), the rate of grade 3/4 infections (18% vs. 26%, p=0.28), or the rate of 2-CdA-related septic deaths (2% vs. 1%, p=0.64). In conclusion, the results of our randomized study indicate that HCL treatment based on weekly 2-CdA infusions for 6 weeks is equally effective, but not safer than standard 5-day 2-CdA protocol.
Recombinant Bispecific Monoclonal Antibody (bsMAb) Against CD20 and CD22 Active In Vitro and In Vivo Against B-Cell Lymphomas.
Authors: Qu Zhengxing , Cardillo Thomas M. , Shi Victoria , Delaney Diana L. , Hansen Hans J. , Chang Chien-Hsing , Goldenberg David M. 
Published: October 2019

Abstract
Background: Preclinical and clinical results suggest improved anti-lymphoma activity of combining anti-CD20 and anti-CD22 MAbs. Our aim was to develop a recombinant bispecific MAb against CD20 and CD22 antigens, and to evaluate its anti-tumor potency compared to the parental MAbs.
Methods: Tetravalent anti-CD20/CD22 bsMAb in the form of anti-CD20 IgG linked to two anti-CD22 scFv’s was prepared recombinantly. The ability of the bsMAb to inhibit cell growth and mediate CDC and ADCC was evaluated by cell-based assays. Phosphorylation and distribution of CD22 in B-lymphoma cells treated with the bsMAb were studied by immunoblotting. The extension of survival of disseminated Daudi lymphoma cells in SCID mice also was evalauted.
Results: In contrast to the parental anti-CD22 MAb, epratuzumab, the bsMAb did not internalize in Ramos cells. In CDC tests, the bsMAb showed no cytotoxic effects, similar to epratuzumab, although it did bind C1q complement protein, unlike epratuzumab. In ADCC, the bsMAb was as potent as the parental humanized anti-CD20 Mab, hA20, in inducing target-cell lysis. The anti-CD20/CD22 bsMAb has distinct effects on NHL B-cell lines compared to each parental monospecific MAb or in combination:
<10 nM bsMAb causes cells to aggregate; in the soluble, non-crosslinked form, while none of the parental MAbs alone or mixed had significant anti-proliferative activity, the recombinant bsMAb was strongly anti-proliferative; the anti-proliferation activities induced by an anti-IgM Ab and the bsMAb were synergistic; and the bsMAb resulted in rapid redistribution of CD22 into detergent-resistant membrane microdomains on the cell surface.
Initial animal studies show that the bsMab significantly extended survival over control SCID mice.
Conclusion: The recombinantly fused anti-CD20/CD22 bsMAb has new properties compared to the parental monospecific MAbs, and may represent a new class of potential therapeutic agents that could replace binary combinations of antibodies.
Histone Deacetylase Inhibitor Promotes Rituximab-Induced Apoptosis in Non-Hodgkin’s B-Lymphoma Cells by NF-kB-Mediated Bcl-2/Bcl-XL Downregulation and c-Myc Degradation.
Authors: Zhao Weili , Wang Lan , Liu Yuanhua , Yan Jinsong , Leboeuf Christophe , Janin Anne , Chen Zhu , Chen Saijuan 
Published: October 2019

Abstract
The anti-CD20 monoclonal antibody rituximab has shown promising results in the clinical treatment of patients with B-cell non-Hodgkin’s lymphoma (B-NHL). However, its therapeutic effect could still be improved. This study examined the anti-tumor activity of rituximab combined with histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) in CD20-positivie B-NHL cell lines, as well as in primary B-NHL cells and a murine B-NHL model. The combination treatment sensitized B-NHL cells to apoptosis in a synergistic manner, concomitant with Bcl-2/Bcl-XL downregulation, mitochondrial instability, and caspase activation. Particularly in Daudi cells relatively insensitive to rituximab, these events were associated with nuclear factor-kB (NF-kB) inactivation. SAHA presented functional complementation with rituximab, through decreasing IKKa/b and IkBa phosphorylation, thus preventing NF-kB nuclear translocation. In addition, SAHA induced IkBa cleavage to a stable inhibitory form and caused NF-kB degradation in response to caspase-3 activation. As an independent approach, co-administration of rituximab and SAHA resulted in a clear decline in levels of ERK cascade members, including extracellular-signal-regulated kinase (erk) itself, upstream Raf-1, mitogen-activated protein kinase/ERK Kinase Kinase-1 (mekk1), and mekk2, as well as their downstream transcription factor target c-myc. By western blot, c-Myc protein was subsequently downregulated when treated with rituximab or SAHA, and the degradation was most significant in combination group. More importantly, rituximab-SAHA combination significantly promoted primary B-NHL cells apoptosis and improved the survival time of a SCID mouse lymphoma model established with intravenous injection of Daudi cells. Terminal deoxytransferase-catalyzed DNA nick-end labeling and ultrastructural study revealed increased apoptotic lymphoma cells on mice spleen sections of combination group. Taken together, these findings emphasized the value of targeting apoptosis signaling pathway in lymphoma therapy. Rituximab in conjunction with histone deacetylase inhibitor may represent a novel strategy in treating patients with B-NHL.
Molecular and Functional Effects of the Novel MEK Inhibitor PD0325901 in Preclinical Models of Human Leukemias.
Authors: Milella Michele , Ricciardi Maria Rosaria , Gregorj Chiara , De Cave Fabiana , Abrams Steven L. , Steelman Linda S. , Chiaretti Sabina , Konopleva Marina , Petrucci Maria Teresa , Cognetti Francesco , Foa Robert , Andreeff Michael , McCubrey James , Tafuri Agostino 
Published: October 2019

Abstract
The Raf/MEK/ERK signaling module plays a pivotal role in the regulation of cell proliferation, survival, and differentiation. Our group, among others, has recently demonstrated that this pathway is frequently dysregulated in hematological malignancies and may constitute an attractive therapeutic target, particularly in AML. Here we investigated the effects of PD0325901, a novel MEK inhibitor, on phospho-protein expression, gene expression profiles, cell proliferation, and apoptosis in cell line models of AML, ALL, multiple myeloma (MM), ex vivo-cultured primary AML blasts, and oncogene-transformed hematopoietic cells. AML cell lines (OCI-AML2, OCI-AML3, HL-60) were strikingly sensitive to PD0325901 (IC50: 5–19 nM), NB4 (APL) and U266 (MM) showed intermediate sensitivity (IC50: 822 and 724 nM), while all the lymphoid cell lines tested and the myeloid cell lines U937 and KG1 were resistant (IC50 > 1000 nM). Cell growth inhibition was due to inhibition of cell cycle progression and induction of apoptosis. A statistically significant reduction in the proportion of S-phase cells (p=0.01) and increase in the percentage of apoptotic cells (p=0.019) was also observed in 18 primary AML samples in response to 100 nM PD0325901. Analysis of the correlation between sensitivity/resistance to PD0325901 and Ras/Raf mutation status is currently ongoing. PD0325901 effects were also examined in a panel of IL-3-dependent murine myeloid FDC-P1 cell lines transformed to grow in response to 11 different oncogenes in the absence of IL-3. Fms-, Ras-, Raf-1-, B-Raf-, MEK1-, IGF-1R-, and STAT5a-transformed FDC-P1 cells were very sensitive to PD0325901 (IC50: ~ 1 nM), while A-Raf-, BCR-ABL-, EGFR- or Src-transformed cells were 10 to 100 fold less sensitive (IC50: 10 to 100 nM); the parental, IL-3 dependent FDC-P1 cell line had an IC50 > 1000 nM. Analysis of the phosphorylation levels of 18 different target proteins after treatment with 10 nM PD0325901 showed a 5- to 8-fold reduction in ERK-1/2, observed only in sensitive cell lines, and a 2-fold reduction in JNK and STAT3 phosphorylation. PD0325901 (10 nM) treatment also profoundly altered the gene expression profile of the sensitive cell line OCI-AML3: 96 genes were modulated after 24 h (37 up- and 59 down-regulated), most of which involved in cell cycle regulation. Changes in cyclin D1 and D3, cyclin E, and cdc 25A were also validated at the protein level. Overall, PD0325901 shows potent growth-inhibitory and pro-apoptotic activity, indicating that MEK may be an appropriate therapeutic target in an array of different hematological malignancies. Further preclinical/clinical development of this compound is warranted, particularly in myeloid leukemias.
A Critical Role for the Retinoblastoma Tumor Suppressor Gene in Hematopoietic Stem Cells.
Authors: Geiger Hartmut , Filippi Marie-Dominique , Kalfa Theodosia A. , Daria Deidre 
Published: October 2019

Abstract
The retinoblastoma tumor suppressor protein (RB) plays important roles in the control of the cell cycle, DNA-damage checkpoint, differentiation and apoptosis. It is estimated that RB is dysfunctional/inactivated in up to 40% of human leukemias. Positive as well as inhibitory signals are integrated into the phosphorylation of the RB protein to regulate the G1 to S-phase progression of the cell cycle. Despite the importance of RB in leukemia, the consequences of loss of RB on hematopoietic stem and progenitor cell (HSPC) function in vivo are still not clear and have been controversially discussed. Using Cre-enzyme expression driven by the hematopoietic specific Vav1-promotor, we generated mice that are constitutively deficient in RB (hemRb−/− animals) in HSPCs. HemRb−/− mice showed anemia with an increased number of reticulocytes in PB, consistent with a published role of RB in erythroid differentiation. In addition, the frequency of Mac-1 positive cells in BM was increased to 67% compared to 47% in control animals, whereas the frequency of B220 positive B-lymphoid cells was almost 10-fold reduced, without affecting the T-lymphoid compartment. HemRb−/− mice possessed a 3-fold enlarged spleen with a 5-fold increased number of colony-forming cells (CFCs) and severe extramedullary hematopoiesis, a phenotype also reported for animals transplanted with Rb−/− fetal liver cells.
BM of hemRb−/− mice showed an almost 3-fold reduction of HSC frequency, measured by the cobblestone-area forming cell assay (CAFC) assay, but not a decrease in the number of HSCs determined by cell surface staining and flow cytometry. Upon transplantation into NOD/SCID animals or upon competitive transplantation into C57BL/6. CD45.1 animals, HSPCs from hemRb−/− mice contributed 4 to 6-fold less to hematopoiesis. HSPCs from hemRb−/− animals were neither impaired in their ability to home to the BM, nor did they show increased apoptosis. Finally, we detected a significant 4-fold decrease in stem cell function/numbers upon stress caused by 5-FU treatment in hemRB−/− mice compared to control animals. We conclude that upon transplantation/stress, HSPCs from hemRb−/− animals are impaired in their self-renewal function. HemRb−/− animals also showed a 2-fold increase in the frequency of CFCs in peripheral blood. As we detected no increased leukemia incidence in the hemRb−/− animals (now up to 1 year of age), loss of the tumor suppressor RB in hematopoietic cells might be regarded as necessary, but not sufficient for causing early onset leukemia. In summary, loss of RB results in context/localization dependent phenotypes in the hematopoietic hierarchy, influencing stem and progenitor cells in function, localization and differentiation ability.
Differentiation of Non-Adherent Hematopoietic Stem Cells from Umbilical Cord Blood Cells into Adherent Hepatocytic Lineage.
Authors: Peters Rowayda Elias , Mock Melissa , Meier Peter , Renner Christoph , Knuth Alexander , Stieger Bruno 
Published: October 2019

Abstract
The liver consists of a variety of different cell types, the vast majority of which are hepatocytes. It has been shown that adult, as well as umbilical cord blood (UCB) mesenchymal stem cells (MSC) are capable of differentiation into mesenchymal and non-mesenchymal tissues including hepatocytes. Only a limited number of UCB units (20%) such as frozen, unfractionated and concentrate leukocytes induced by hydroxyethyl starch volume reduced UCB units can generate MSC. In light of this, we have developed the technology to generate potent MSC from all frozen UCB samples tested (3/3). In the present study, the incubation of thawed out UCB mononuclear cells (MNC) and non-selected CD34+ cells in the presence of SCF (25ng/ml), FLt-3 (25ng/ml), MGDF (10ng/ml) & IL-6 (20ng/ml) and 10% human serum in stroma-free liquid culture not only generated long term expansion of transplantable UCB hematopoietic stem cells (non-adherent) (Peters et al., 2004), but also long-term expansion of MSC (adherent cells). Adherent cells were enriched by medium changes followed by trypsinization and subsequent culture and passing on fibronectin in the presence of 10% human serum and 30ng/ml bFGF. The stroma-free liquid cultures were tested for the production of hematopoietic stem cells (HSC), as well as MSC over a period of 15 weeks; MSC increased throughout expansion of HSC. We used the CFU-Fibroblast assay to demonstrate MSC activity in stromal cell formation in vitro. Expanded MSC between passages 3–5 were plated using MesenCult™ (Stem Cell Technologies). After 14 days incubation at 37oC, 5% CO2, very large and small CFU-fibroblast colonies generated from 105 MNC/ml (initiated on Day 0 in stroma-free liquid culture) were continuously detected throughout expansion. In order to test the capacity of MSC to differentiate into hepatocytes, cells were cultured in DMEM supplemented with dexamethasone and 25ng/ml HGF, the latter of which was replaced with 50ng/ml oncostatin M after incubation day 14. The cells were able to expand to cell lines and took on the common hexagonal shape characteristic of hepatocytes; this parameter was used as a primary screening criterion. In addition, the hepatocyte-like cells were further assessed by reverse transcription-polymerase chain reaction and found to express mRNA for albumin, as well as two hepatocyte-specific bile salt transport proteins, basolateral bile transport system NTCP and the canalicular bile salt export pump BSEP. These data demonstrate the presence of pluripotent stem cells in UCB with the capacity to differentiate into a hepatocytic lineage.The research in this area has great potential, both with respect to future application in patients with end-stage liver disease, as well as for learning more about the role of MSC in new clinical cellular therapies.
Derivation of SSEA4-/CD73+ Mesenchymal Stem Cells from Human Embryonic Stem Cells.
Authors: Trivedi Parul , Hematti Peiman 
Published: October 2019

Abstract
Human embryonic stem cells (hESCs) could potentially provide a renewable source of different types of cells for cell therapy applications. Recently, mesenchymal stem cells (MSCs) have been derived from hESCs either through co-culturing with murine OP9 bone marrow stromal cell line or directly from hESCs without co-culturing with OP9 cells. Although the latter methodology is clinically advantageous over co-culturing with an animal cell layer those mesenchymal cells were reported to be positive for SSEA4. SSEA4 is a marker of undifferentiated hESCs and thus the presence of this marker on hESC-derived cells could potentially be problematic for clinical applications. We have recently achieved a novel and reproducible methodology for deriving a pure population of SSEA4-/CD73+ MSCs from federally approved hESC lines H1 and H9. To initiate the differentiation of hESCs to MSCs, we cultured undifferentiated hESCs on matrigel plates in murine embryonic fibroblast conditioned media with media changes every 3 days. Under these culture conditions a portion of embryonic stem cells differentiated into fibroblast looking cells. Through a multi-step process which involved the use of a culture methodology similar to what is being used to culture bone marrow (BM)-derived MSCs, and passaging cultured cells at defined time points we were able to derive a pure population of cells that were uniformly positive for MSC marker CD73 in about a 4-weeks period. These cells had fibroblast/mesenchymal looking morphology, and expressed cell surface marker antigens similar to what has been reported for adult human BM-derived MSCs: they are positive for CD29, CD44, CD54, CD71, CD90, glycophorin A, CD105, and were negative for hematopoietic markers such as CD34 and CD45. Similar to adult BM-derived MSCs these cells express HLA class-I antigens but not class-II antigens. Using established differentiation protocols we could differentiate the hESC-derived CD73+ MSCs into adipocytes, osteocytes, and chondrocytes as verified by immunohistochemistry and RT-PCR assays. So far we have grown these CD73+ MSCs up to passages 15–18. These cells retained their differentiation potential, and were karotypically normal when tested at passage 12. Most importantly, we did not observe any MSCs that were double positive for CD73 and SSEA4 antigen at any time point during our experiments. MSCs from a variety of fetal and adult sources are in various stages of clinical trials with some encouraging preliminary results. Our hESC-derived MSCs that are very similar to adult BM-derived MSCs regarding their growth and morphologic properties, immunophenotypic characteristics, differentiation potential, and importantly are devoid of hESC marker SSEA4 could potentially provide a novel source of MSCs for clinical applications.
Inhibition of Bcl-2 Signaling by Small Molecule BH3 Inhhibitor GX15-070 as a Novel Therapeutic Strategy in AML.
Authors: Watt Julie C. , Konopleva Marina , Contractor Rooha , Samudio Ismael , Harris David , Estrov Zeev , Viallet Jean , Andreeff Michael 
Published: October 2019

Abstract
GX15-070 is a novel cycloprodigiosin derived small molecule BH3 inhibitor that binds with moderate affinity to all antiapoptotic Bcl-2 family members, including Mcl-1, and is currently undergoing Phase I clinical trials in leukemias. In this study, we investigated the activity of GX15-070 in acute myeloid leukemia (AML) cell lines and primary AML samples. GX15-070 inhibited cell growth of HL-60, U937, OCI-AML3 and KG-1 cell lines at IC50’s of 0.1, 0.5, 0.5 and 2.5μM, respectively, at 72 hours. Neither overexpression of Bcl-2 or Bcl-XL nor loss of expression of Bax conferred resistance to GX15-070. GX15-070 inhibited Bim/Bcl-2 heterodimerization and induced association of activated Bak with Bax in OCI-AML3 cells, as demonstrated by co-immunoprecipitation studies using CHAPS buffer. This was associated with cytosolic release of cytochrome c followed by an increase in annexin positivity, caspase activation and a decrease in mitochondrial inner membrane potential. Notably, GX15-070 induced cytochrome c release from isolated mitochondria of leukemic cells. GX15-070 synergized with both AraC and the novel BH3 mimetic ABT-737 to induce apoptosis in OCI-AML3 cells, a notoriously chemoresistant cell line (GX15-070 and ABT-737 average CI value 0.3; GX15-070 and AraC average CI value 0.36). In 6/7 primary AML samples, GX15-070 induced apoptosis in CD34+ progenitor cells at an average IC50 of 3.6±1.2μM at 24 hours. GX15-070 potently inhibited clonogenic ability of AML blasts at sub-micromolar doses (58.5±10.6% CFU-Blast at 0.1μM and 38.1±10.5% at 0.25μM, n=7). In summary, BH3 inhibitor GX15-070 induces apoptosis in AML cells via inhibition of association of pro-survival Bcl-2 family proteins and BH3-only proteins, followed by Bax/Bak activation and initiation of the intrinsic apoptotic pathway. Hence, GX15-070 alone or in combination with chemotherapeutic agents may have utility in AML therapy.