bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methylseleninic Acid (MSA) Decreases DNA Synthesis, Induces Cell Death, and Sensitizes Both Rituximab Sensitive and Rituximab-Resistant Non-Hodgkin’s Lymphoma Cell Lines to the Anti-Tumor Activity of Cisplatin and Gemcitabine.
Authors: Hernandez-Ilizaliturri Francisco J. , Ali Minhas , Knight Joy , Rustum Youcef M. , Czuczman Myron S. 
Published: October 2019

Abstract
Selenium (Se) is an essential trace element with antioxidant properties. Examination of the dietary intake of Se in more than 25 countries found an inverse correlation with total age-adjusted cancer mortality. In addition, other investigator had shown that low serum levels of Se correlate with an adverse outcome in patients with diffuse large B-cell lymphoma (DLBCL) undergoing anthracycline-base chemotherapy. Various Se compounds had been developed and are undergoing preclinical testing such as MSA or Sodium selenite (SS). SS has been shown to decrease PKCg activity and induce apoptosis in murine lymphomas. In an attempt to further evaluate the role of Se in human lymphomas we studied the effects of MSA in a panel of rituximab-sensitive (RSCL) and rituximab-resistant cell lines (RRCL). Resistant clones were generated by chronic exposure of Raji, RL or DHL-4 cells to escalating doses of rituximab with (4RH) or without (2R) human complement. Functional assays were performed to demonstrate decrease in rituximab sensitivity on RRCL. In addition, resistance to chemotherapy (CDDP, doxorubicin, vincristine, etc.) agents was demonstrated in RRCL. Lymphoma cells were exposed in vitro to MSA (0 to 5mM) with or without CDDP (0 to 10mM) or gemcitabine (0 to 10mM). Following a 72 hour-period of MSA-drug exposure, changes in mitochondrial potential were determined by alamar blue reduction measured at 30 minutes intervals over a 48 hr period. In addition, changes in DNA synthesis and cell proliferation following drug exposure were performed using standard [3H]-thymidine incorporation assays. MSA induced dose-dependent cell death and a decrease in DNA synthesis in all the cell lines tested (both RSCL and RRCL). Up to a 50% reduction in mitochondrial potential and cell viability was observed in RRCL or RSCL exposed to 5mM of MSA. Incubation of RSCL and RRCL to 5mM of MSA induced synergistic cytotoxic and anti-proliferative effects when combined with CDDP or gemcitabine. Our data demonstrates that MSA is active against various RSCL and RRCL and potentiates the anti-tumor effects of chemotherapy agents. Our findings strongly suggest that MSA added to systemic chemotherapy (i.e. combination of gemcitabine and cisplatin) may result in a novel and potent salvage regimen against relapsed/refractory B-cell lymphomas.
Blast Transformation in a Patient with Primary Myelofibrosis Initiated from JAK2 V617F Progenitor.
Authors: Swierczek Sabina I. , Yoon Donghoon , Prchal Josef T. 
Published: October 2019

Abstract
Myeloproliferative disorders (MPDs) are caused by clonal proliferation arising from a single multi-lineage stem cell. The JAK2 V617F mutation has been reported in greater than 90% of patients with polycythemia vera (PV), and ∼50% of patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF). However, several studies have indicated that the JAK2 V617F mutation is not an MPD initiating mutation but rather represents clonal evolution of these MPDs. Jelinek and colleagues first reported that most PV transformed acute leukemias are JAK2 V617F negative (Jelinek, Blood, 2005 106:3370). More recently, the role of the JAK2 V617F mutation in leukemic transformation in 27 patients with MPDs revealed that most JAK2 V617F -positive MPD patients transformed to a JAK2 V617F -negative AML (Theocharides, Blood, 2007 110:375); however, in the 4 patients with an apparent JAK2 V617F -positive leukemia clonality of leukemic blasts and mature granulocytes was not determined. Two models proposed by Theocharides et al may explain these findings. First, MPD and AML represent 2 independent clones that arose de novo from different progenitors. Second, MPD and AML are 2 subclones derived from a common progenitor. Here, we describe a woman with PMF with transformation to AML. We determined her JAK2 V617F mutation status by sensitive and quantitative real-time PCR (Nussenzveig, Exp Hematol, 2007 3:32). At the time of her transformation to AML, her normal appearing peripheral blood granulocytes were purified and the frequency of mutant JAK2 allele T was 6%. However, all FACS-sorter isolated CD34+ cells (enriched to 95% purity) were heterozygous for the JAK2 V617F mutation. To determine if MPD and AML clones arose de novo or from the same progenitor, we performed clonality studies using a newly developed sensitive and quantitative real-time PCR based on the X-chromosome inactivation principle using transcriptional clonality assays in granulocytes and CD34+ purified cells from peripheral blood at both stages of disease (see Swierczek et al, abstract, this meeting). When this woman’s PMF was first discovered, hematopoiesis was clonal, based on heterozygosity for three X-chromosome genes, FHL1, G6PD and IDS (Liu, Blood, 2003 101:3294) and their single allelic expression in granulocytes and platelets. At the time of leukemic transformation, both her granulocytes and leukemic CD34+ cells expressed all three identical isoforms from the same parental X chromosome. Our findings indicate that leukemic transformation does not invariably arise from a JAK2 V617F negative progenitor. This has important implication for therapy of MPDs with JAK2 V617F inhibitors, as these would not prevent leukemic transformation. It remains to be determined if the JAK2 background of leukemic progenitors is variable, and if there are differences between PV and PMF.
High Frequency of Surface Immunoglobulin IgG in B-Cell Chronic Lymphocytic Leukaemia.
Authors: Wiseman Catherine , Giustiniani Jerome , Mikkelsen Lene , Macey Marion , Goff Lindsey , Gribben John , Agrawal Samir 
Published: October 2019

Abstract
Background: A common diagnostic feature of chronic lymphocytic leukaemia (CLL) is the weak surface immunoglobulin (sIg) expression of the IgM/D isotypes. The occurrence of sIgG is believed to be an atypical finding in CLL.
Aims: To demonstrate that sIgG expression is a real and not artefactual by molecular and functional assays.
Methods: 194 unselected, consecutive cases of CLL were analysed during routine diagnostic testing for sIgG and sIgM. Flow cytometry was performed using fresh whole blood and red cell lysis (Pharmalyse solution, BD). For confirmation of these results and demonstration of functionality, we used 4-colour flow cytometry, PCR for mRNA detection, proliferation assay (3H incorporation), and calcium flux assay.
Results: 23% (44/194) of all CLL cases displayed sIgG, with 39 being sIgG+ alone. PCR results showed a distinct band indicating the presence of mRNA for IgG. Four-colour flow cytometry identified single cells that co-expressed CD19/CD160/sIgG and ruled out sIgM expression. In vitro proliferation assays demonstrated that sIgG is functional when triggered by F(Ab’)2 fragments specific for sIgG isotype. The strength of the signal in one case after stimulation via sIgG led to a 3.5-fold increase in cellular proliferation. Calcium flux assays also demonstrated that the IgG isotype was functional, one case showing a 50% increase in fluorescence intensity after stimulation via sIgG.
Discussion: 23% of CLL cases have sIgG expression. In addition to a high frequency of sIgG expression, this study has shown sIgG to be capable of signalling. If antigen-drive is important in CLL, an IgG B-cell receptor should have higher affinity for a putative antigen, which potentially would be a poor prognostic feature. However, such cases would also be expected to show mutated VH genes, indicating a better prognosis. Further study is required to elucidate the pathological significance of sIgG expression and its role in CLL.
Dose-Reduced Conditioning Followed by Allogeneic Stem Cell Transplantation in Patients with Myelofibrosis. Results from a Multicenter Prospective Trial of the Chronic Leukemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).
Authors: Kroeger Nicolaus , Holler Ernst , Kobbe Guido , Bornhaeuser Martin , Schwerdtfeger Rainer , Nagler Arnon , Bethge Wolfgang , Stelljes Matthias , Uharek Lutz , Wandt Hannes , van Os Marleen , Burchert Andreas , Corradini Paolo , Schubert Joerg , Kaufmann Martin , Dreger Peter , Wulf Gerald , Einsele Hermann , Gramatzki Martin , Zabelina Tatjana , Bacher Ulrike , Zander Axel , Heinzelmann Marion , Kvasnicka Michael , Thiele Juergen , Niederwieser Dietger , de Witte Theo 
Published: October 2019

Abstract
The major limitation of allogeneic stem cell transplantatiopn (SCT) in patients (pts) with myelofibrosis is the high treatment related mortality. We performed a prospective multicenter trial of a dose-reduced conditioning regimen, consisting of busulfan (10 mg/kg orally or 8mg/kg i.v), fludarabine (180 mg/m2) and anti-thymocyte globulin (ATG Fresenius: 30–60 mg/kg) followed by allogeneic SCT in pts with myelofibrosis. From 2002 to 2006, 104 pts with a median age of 55 years (range: 32–68) andlow risk with constitutional symptoms (18%) or intermediate risk (n= 58%) and high risk (n=19%) were included. Cytogenetic abnormalities and JAK2 mutation were noted in 22% and 48%, respectively. Bone marrow histology showed advanced fibrosis (MF 2 and 3) in all pts. All but 3 pts received peripheral blood stem cells as graft source either from related (n=33) or unrelated donor (n=71). All but one (1%) pts showed leukocyte and platelet engraftment after a median of 18 and 21 days, respectively. The median duration of leukocyte aplasia was 9 days (range: 3–21). Acute GvHD grade II to IV occurred in 19% and severe aGvHD III/IV in 7%, while chronic GvHD was seen in 32% of the pts. Non-relapse mortality at 1 year was 19% (95% CI: 11–27%) and significantly lower for pts younger than 50 years of age (0% vs 27%, p=0.004) and for pts with low risk vs intermediate/high risk disease (0% vs 27%, p= 0.02). The cumulative incidence of relapse at 3 years was 29% (95%CI: 15–43%). The 3 year overall (OS) and event-free survival (EFS) was 70% (95% CI 60–80%) and 55% (95% CI 42–68%). Significant factors for improved 3 year OS and EFS were age less than 50 years (92% vs 62%, p=0.003 and 79% vs 46%, p= 0,004) and low vs intermediate/high risk (100% vs 62%, p=0.01 and 72% vs 48%, p= 0.02), while no impact on survival was seen for cytogenetic abnormalities, JAK2 mutation status and donor (related vs unrelated). These prospective multicenter study show excellent outcome of an busulafan/fludarabine based reduced conditioning regimen followed by allogeneic SCT in pts with myelofibrosis.
Ex Vivo Graft Purging and Expansion of Autologous Mobilized Peripheral Blood Progenitor Cell (PBPC) Products from Patients with Multiple Myeloma (MM).
Authors: Yang Hong , Robinson Simon N. , Nieto Yago , Giralt Sergio A. , Jones Roy B. , Decker William K. , Xing Dongxia , Steiner David , Champlin Richard E. , Ng Jingjing , Thomas Michael W. , de Lima Marcos , Shpall Elizabeth J. 
Published: October 2019

Abstract
Introduction: Autologous PBPC transplantation has become the treatment of choice for selected MM patients. Autografts are often contaminated with MM cells which could be a source of post-transplant relapse. We elected to develop a graft manipulation procedure to purge tumor cells from the autograft without compromising its normal reconstituting activity. Previous studies have shown that bortezomib (Velcade, Millenium Pharmaceuticals, Inc., Cambridge, MA) can kill CD138+ MM cells, with little effect on CD138− B cells. However, the anti-CD20 monoclonal antibody, rituximab (Rituxan, Genentech, Inc., San Francisco, CA) has been shown to kill CD138− B cells, the putative MM “stem cells” population. Therefore we investigated whether an optimized combination of bortezomib and rituximab might effectively eradicate tumor cells from PBPC products. Previous studies1 have also suggested that tumor cells can also be selectively purged by ex vivo culture while expanding the normal hematopoietic progenitors. Thus, we incorporated an ex vivo culture step to optimize MM cell depletion and expansion of the reconstituting normal progenitors.
Methods: CD138+ cells were depleted from the thawed PBPC of MM patients using the midiMACS device (Miltenyi Inc, Auburn, CA). The CD138− cells were treated for 24 hrs with 10 or 20 μg/ml rituximab followed by 20nM or 80nM bortezomib for 16hrs. Cells were then washed and ex vivo-expanded using an allogeneic normal marrow donor-derived mesenchymal stem cell (MSC) co-culture technique as previously reported.2 At the end of culture, cells were evaluated for total viable cells, expression of CD138, CD20, CD19, CD34, CD45 by flow cytometry and colony-forming cell (CFC) content in methylcellulose assays (StemCell Technologies, Vancouver, BC).
Results: CD138+, CD138−/CD20+ or CD138−/CD20+/CD19+ cells were depleted in the MM PBPC products from patients when treated with bortezomib (20nM) and rituximab (20 μg/ml) followed by ex vivo culture.(Fig 1) Compared with input control, TNC increased by 6–72 fold and absolute numbers of CD34+ cells increased by approximately 3–9 fold. (See representative data Fig 2)
Conclusion: Treating CD138-depleted MM PBPC products with bortezomib, rituximab and 2 weeks of ex vivo culture depleted CD138+ malignant plasma cells and CD138− B cells (MM “stem cells”). An estimated >4 log tumor depletion from a mobilized PBPC product was achieved, while the use of ex vivo expansion culture not only preserved but increased the number of normal hematopoietic progenitors. Further refinements of this procedure are in progress and will be tested clinically.
Figure Figure Figure Figure
Syk Kinase Inhibition by R406 Inhibits BCR Mediated B Cell Proliferation and Interferes with BCR Signal Transduction in Primary Tumor Samples.
Authors: Sharman Jeff P. , Irish Jonathan , Hatton Olivia , Martinez Olivia , Levy Ronald 
Published: October 2019

Abstract
Background: B cells require B cell receptor (BCR) mediated survival signals during differentiation and throughout maturity. However, the CD79a/b signaling subunit of the BCR lacks independent kinase function and requires Syk kinase activity to activate the majority of downstream signaling effectors in the BCR signal transduction cascade. We have previously shown that inactivating Syk kinase with R406, a novel small molecule tyrosine kinase inhibitor, selectively kills B cells from primary human tumor samples and B cell lines (Sharman et. al ASCO 2007, Abstract # 3600). In addition, we have shown that Syk signaling is abnormally rapid, intense, and long-lived in primary human follicular lymphoma B cells (Irish et. al Blood2006108(9) 3135–3142). We hypothesized that R406 would prevent BCR mediated proliferation of normal B cells and interfere with BCR signaling in primary B lymphoma tumor samples.
Methods: Normal peripheral blood B cells were evaluated with 3H-thymidine incorporation following BCR stimulation with anti-IgM and treatment with several concentrations of R406. Phosphospecific flow cytometry was used to evaluate signal transduction in single cell suspensions derived from primary lymphoma tumor samples and cell lines pretreated with R406.
Results: Peripheral blood B cells proliferate in response to BCR stimulation. This proliferation is inhibited by R406 with IC50 of approximately 100 nM and IC100 at 1250 nM. Several concentrations of R406 were used to inhibit BCR signaling in primary tumor samples. At the lowest dose 50nM, there was little impact on downstream signaling in most samples. At the highest dose tested, 2500 nM, phosphorylation of SFK, Syk, Btk, c-Cbl, p38, Stat-3, Stat-5, Erk, and Akt was completely blocked in all patients. At this same dose, R406 did not inhibit Erk phosphorylation in response to PMA in cell lines.
Conclusions: At pharmacologically relevant concentrations, R406 prevents peripheral blood B cell proliferation in response to BCR stimulation and completely blocks phosphorylation of all proteins evaluated following BCR stimulation in primary tumor samples. Signaling from PKC to Erk which classically involves Ras, Raf, and MEK is undisturbed at maximum drug concentrations. These findings are consistent with the hypothesis that Syk determines the phosphorylation status of most proteins within the BCR signaling cascade following BCR stimulation. Since B cells require BCR mediated survival signals, the anti-BCR signaling effect of R406 may be effective against B cell neoplasms. This idea is currently being tested in a phase I/II clinical trial using an orally bioavailable form of R406 in patients with relapsed and refractory B cell NHL.
Significance of Telomere Length Measurement in the Diagnosis of Dyskeratosis Congenita.
Authors: Du Hong-Yan , Pumbo Elena , Shimamura Akiko , Vlachos Adrianna , Lipton Jeffrey M. , Goldman Fred , Wilson David B. , Mason Philip , Bessler Monica 
Published: October 2019

Abstract
Dyskeratosis congenita (DC) is a rare inherited bone marrow failure (BMF) syndrome. The classical features of DC include nail dystrophy, abnormal skin pigmentation, and mucosal leukoplakia. The diagnosis of DC can be difficult. Originally, the diagnosis was based on the presence of the classical mucocutaneous features. However, the identification of four genes responsible for DC (DKC1, TERC, TERT, and NOP10) showed that these mucocutaneous features are only present in a proportion of patients with DC. Additionally, screening for mutations in the affected genes is expensive and is negative in about 50% of patients with classical features of DC. The products of the genes mutated in DC are the components of the telomerase ribonucleoprotein complex, which is essential for telomere maintenance. Therefore it has been postulated that DC is a disease arising from excessive telomere shortening. Here we examined whether the measurement of telomeres could be used as a screening test to identify individuals with DC. For this purpose we examined telomere length in peripheral blood mononuclear cells from 169 patients who presented with bone marrow failure including 17 patients with DC, diagnosed by the presence of classical cutaneous features or the identification of mutations in DKC1, TERC or TERT, 28 patients with paroxysmal nocturnal hemoglobinuria, 25 patients with Diamond Blackfan anemia, 5 patients with Shwachman-Diamond syndrome, 8 patients with myelodysplastic syndrome, and 74 patients with aplastic anemia of unknown cause classified as idiopathic aplastic anemia. In addition we measured telomere length in 12 patients with idiopathic pulmonary fibrosis and in 45 individuals with a de novo deletion of chromosome 5p including the TERT gene. Their telomere lengths were compared with those of 202 age-matched healthy controls. Moreover, mutations were screened in the genes associated with DC. In cases where a mutation was identified, telomere length and mutations were also examined in all the family members. Our results show that all patients with DC and bone marrow failure have very short telomeres far below the first percentile of healthy controls. Not all mutation carriers, including some carriers of apparently dominant mutations, have very short telomeres. What is more, very short telomeres could be found in healthy individuals in these families, some of whom were not mutation carriers. These findings indicate that in patients with BMF the measurement of telomere length is a sensitive screening method for DC, whether very short telomeres in this setting are also specific for DC remains to be determined. However, in contrast to a previous study, we find that telomere length does not always identify mutation carriers in the families of DC.
Retrospective Comparison of Transplant Outcomes in Patients with Multiple Myeloma According to Induction Therapy with Thalidomide/Dexamethasone (TD) with or without Bortezomib (VTD).
Authors: Giralt Sergio , Thandi Rupi , Qazilbash Muzaffar , Mendoza Floralyn , Han Eric , Hosing Chitra , Wang Michael , Thomas Sheeba , Alexanian Raymond , Champlin Richard , Weber Donna 
Published: October 2019

Abstract
Background: Thalidomide/Dexamethasone (TD) has become one of the most commonly used induction therapies for patients with symptomatic multiple myeloma (MM) eligible for high dose therapy (HDT) intensification with autologous stem cell transplant (ASCT). Bortezomib (Velcade) has been added to the combination of TD (VTD) in an effort to reduce MM tumor burden further prior to HDT.The impact of this addition on HDT outcomes has not been fully explored.
Purpose: To determine the impact of the addition of bortezomib to TD induction therapy in patients with MM undergoing HDT and ASCT consolidation.
Patients and Methods: Patients were eligible for this analysis if they had undergone HDT with ASCT for first remission consolidation or primary refractory disease within 12 months of diagnosis between 9/03 and 12/05 and had received either TD or VTD as induction therapy. Patients receiving VTD after TD were excluded. Patients receiving more than 1 chemo regimen other than TD or VTD were excluded. Chemomobilization was NOT considered an exclusion criteria. Results A total of 78 patients qualified for the analysis (27 VTD; 51 TD). Patient and treatment characteristics are summarized in table 1. In brief, the patients receiving VTD had a higher rate of cytogenetic abnormalities and received less cycles of chemotherapy prior to SCT. Although pre-SCT response rates were similar between patients receiving VTD or TD (95% vs 92%) there was a trend for a higher CR rate in the VTD group (15% vs 6%). Post transplants response rates assessed between 3–6 months demonstrated that 28% and 38% of VTD patients achieved near CR and CR respectively while 19% and 23% had these responses post TD induction. There was no difference in 2 year OS and PFS among patients receiving VTD or TD (91% vs 81% and 35% and 56% respectively).
Conclusion: Both VTD and TD as induction treatment are associated with high response rates prior to SCT as well as 6 months post SCT. In this retrospective analysis no survival benefit was seen for induction therapy with VTD over TD, despite higher near CR and CR rates. However randomized trials need to be performed addressing type of induction as well as duration of induction therapy prior to high dose therapy consolidation.
Patient and Treatment Characteristics Variables VTD TD N 27 51 Median Age 54 (34–71) 56 (34–71) %ISS> 1 76% 65% % CG Abnormal 37% 19% p=.009 B2M @ Dx 2.99 3.19 Cycles Prior to SCT 2 4 p=.00009 % Mel 200 74% 69% Post SCT Maintenance 15/27 23/51