bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequent clonal loss of heterozygosity but scarcity of microsatellite instability at chromosomal breakpoint cluster regions in adult leukemias
Authors: Pabst T , Schwaller J , Bellomo MJ , Oestreicher M , Muhlematter D , Tichelli A , Tobler A , Fey MF 
Published: October 2019

Abstract
Microsatellites are important highly polymorphic genetic markers dispersed in the human genome. Using a panel of 22 (CA)n repeat microsatellite markers mapped to recurrent breakpoint cluster regions specifically involved in leukemia, we investigated 114 adult leukemias (25 acute lymphocytic leukemia [ALL], 32 acute myeloid leukemia [AML], 36 chronic lymphocytic leukemia [CLL], and 21 chronic myeloid leukemia [CML] in chronic phase) for somatic mutations at these loci. In each patient, DNA from fresh leukemia samples was analyzed alongside normal constitutive DNA from buccal epithelium. We detected loss of heterozygosity (LOH) in 81 of 114 patients (ALL 16/25, AML 25/32, CLL 30/36, CML 10/21). Deletions were most often seen in ALL at 11q23 and 19p13; in AML at 8q22 and 11q23; in CLL at 13q14.3, 11q13, and 11q23; and in CML at 3q26. Only six deletions were reported in 74 karyotypes analyzed, whereas in these same cases, 91 LOH events were detected by microsatellites. Of 26 leukemias with a normal karyotype, 16 nevertheless showed at least one LOH by microsatellite analysis. Replication errors were found in 10 of 114 patients (8.8%). Thus, microsatellite instability is rare in leukemia in contrast to many solid tumors. Our findings suggest that in adult leukemia, LOH may be an important genetic event in addition to typical chromosomal translocations. LOH may point to the existence of tumor suppressor genes involved in leukemogenesis to a degree that has hitherto been underestimated.
Evaluation of a CD5-specific immunotoxin for treatment of acute graft- versus-host disease after allogeneic marrow transplantation
Authors: Martin PJ , Nelson BJ , Appelbaum FR , Anasetti C , Deeg HJ , Hansen JA , McDonald GB , Nash RA , Sullivan KM , Witherspoon RP , Scannon PJ , Friedmann N , Storb R 
Published: October 2019

Abstract
Acute graft-versus-host disease (GVHD) is most often treated with high dose glucocorticoids, but less than half of patients have durable overall improvement. Previous phase I and phase II studies suggested that treatment with a CD5-specific immunotoxin (XomaZyme-CD5 Plus) could ameliorate symptoms of GVHD. In a randomized, double-blind trial, we compared XomaZyme-CD5 Plus and glucocorticoids versus placebo and glucocorticoids as initial therapy for 243 patients who developed acute GVHD after allogeneic marrow transplantation. The study drug (XomaZyme. CD5-Plus or an identical appearing placebo) was administered at a dose of 0.1 mg/kg body weight on each of 14 consecutive days. All patients were treated concomitantly with a standard regimen of methylprednisolone. At the time of entry on study, 94% of patients had a rash, 56% had hyperbilirubinemia, 61% had diarrhea, and 84% had nausea and vomiting. At 3, 4, and 5 weeks after starting treatment, symptom severity was less in the CD5 group than in the placebo group. At 4 weeks, 40% of patients assigned to the CD5 group had complete response compared with 25% of those assigned to the control group (P = .019). At 6 weeks, 44% of patients assigned to the CD5 group had complete response as compared with 38% in the placebo group (P = .36). Clinical extensive chronic GVHD developed in 65% of patients in the CD5 group compared with 72% in the control group (P = .35). Survival at 1 year after treatment was 49% in the CD5 group and 45% in the control group (P = .68). Side effects required close monitoring and appropriate adjustment of treatment. The combined administration of a CD5-specific immunotoxin and glucocorticoids controls GVHD manifestations more effectively than treatment with glucocorticoids alone during the first 5 weeks after starting treatment. Use of this immunotoxin does not result in any long-term clinical benefit for patients with acute GVHD.
Fibronectin improves transduction of reconstituting hematopoietic stem cells by retroviral vectors: evidence of direct viral binding to chymotryptic carboxy-terminal fragments
Authors: Moritz T , Dutt P , Xiao X , Carstanjen D , Vik T , Hanenberg H , Williams DA 
Published: October 2019

Abstract
Efficient transduction of reconstituting hematopoletic stem cells (HSC) is currently only possible by cocultivation of target cells directly on producer cell lines, a method not applicable to human gene therapy protocols. Our laboratory has previously shown adhesion of primitive hematopoletic stem and progenitor cells to the carboxy-terminal 30/35- kD fragment of the extracellular matrix molecule fibronectin (FN 30/35) (Nature 352:438, 1991) and increased transduction of human hematopoietic progenitor cells via retroviral vectors while adherent to this fragment (J Clin Invest 93:1451, 1994). Here we report that (1) transduction of reconstituting murine HSC assayed 12 months after infection with retrovirus supernatant on FN 30/35 is as effective as cocultivation directly on producer cells; (2) recombinant retrovirus particles directly adhere to FN 30/35 in a quantitative and dose- dependent fashion; and (3) increased transduction efficiency on FN 30/ 35 does not appear to be associated with increased cell proliferation or activation of protein phosphorylation typically induced by integrin- fibronectin interactions. Therefore, we speculate that supernatant infection of HSC on FN 30/35 leads to colocalization of retrovirus particles and target cells on FN 30/35 molecule with a large increase in local virus titer presented to the cell. These findings have direct and important implications for the modification of current human gene therapy protocols.
p53 functional impairment and high p21waf1/cip1 expression in human T- cell lymphotropic/leukemia virus type I-transformed T cells
Authors: Cereseto A , Diella F , Mulloy JC , Cara A , Michieli P , Grassmann R , Franchini G , Klotman ME 
Published: October 2019

Abstract
Human T-cell lymphotropic/leukemia virus type I (HTLV-I) is associated with T-cell transformation both in vivo and in vitro. Although some of the mechanisms responsible for transformation remain unknown, increasing evidence supports a direct role of viral as well as dysregulated cellular proteins in transformation. We investigated the potential role of the tumor suppressor gene p53 and of the p53- regulated gene, p21waf1/cip1 (wild-type p53 activated fragment 1/cycling dependent kinases [cdks] interacting protein 1), in HTLV-I- infected T cells. We have found that the majority of HTLV-I-infected T cells have the wild-type p53 gene. However, its function in HTLV-I- transformed cells appears to be impaired, as shown by the lack of appropriate p53-mediated responses to ionizing radiation (IR). Interestingly, the expression of the p53 inducible gene, p21waf1/cip1, is elevated at the messenger ribonucleic acid and protein levels in all HTLV-I-infected T-cell lines examined as well as in Taxl-1, a human T- cell line stably expressing Tax. Additionally, Tax induces upregulation of a p21waf1/cip1 promoter-driven luciferase gene in p53 null cells, and increases p21waf1/cip1 expression in Jurkat T cells. These findings suggest that the Tax protein is at least partially responsible for the p53-independent expression of p21waf1/cip1 in HTLV-I-infected cells. Dysregulation of p53 and p21waf1/cip1 proteins regulating cell-cycle progression, may represent an important step in HTLV-I-induced T-cell transformation.
Human CD34+ hematopoietic progenitors have low, cytokine-unresponsive O6-alkylguanine-DNA alkyltransferase and are sensitive to O6- benzylguanine plus BCNU
Authors: Gerson SL , Phillips W , Kastan M , Dumenco LL , Donovan C 
Published: October 2019

Abstract
Human bone marrow (BM) cells contain low levels of the DNA repair protein, O6-alkylguanine-DNA alkyltransferase, which may explain their susceptibility to nitrosourea-induced cytotoxicity and the development of secondary leukemia after nitrosourea treatment. Isolated CD34+ myeloid progenitors were also found to have low levels of alkyltransferase activity. The level of alkyltransferase in CD34+ cells or in mononuclear BM cells did not increase after incubation with granulocyte-macrophage colony-stimulating factor, interleukin-3, stem cell factor, the combination, or 5637 conditioned medium. BCNU sensitivity remained unchanged as well. In addition, O6-benzylguanine depleted alkyltransferase activity in BM cells at concentrations as low as 1.5 mumol/L after a 1-hour exposure. O6-benzylguanine pretreatment markedly sensitized hematopoietic progenitor colony-forming cells to BCNU, resulting in a reduction in the dose of drug (termed the dose- modification factor) required to inhibit 50% of the colony formation (IC50) of threefold to fivefold. Since, unlike many other cell types, proliferating early (CD34+) hematopoietic precursors do not induce alkyltransferase, myelosuppression may be the dose-limiting toxicity of the combination of O6-benzylguanine plus BCNU in clinical trials.
T-lymphocyte differentiation and proliferation in the absence of the cytoplasmic tail of the common cytokine receptor gamma c chain in a severe combined immune deficiency X1 patient
Authors: Morelon E , Dautry-Varsat A , Le Deist F , Hacein-Bay S , Fischer A , de Saint Basile G 
Published: October 2019

Abstract
Mutation of the gamma c chain common to interleukin-2 (IL-2), IL-4, IL- 7, IL-9, and IL-15 receptors has been shown to be responsible for the X chromosome-linked severe combined immune deficiency (SCIDX1). Human SCIDX1 patients are characterized by an absence of T and natural killer cell differentiation. We report the case of a SCIDX1 patient who first had few detectable peripheral T cells, then developed, after haploidentical T-depleted bone marrow transplantation (BMT), up to 2,000/microL autologous T cells. These T cells have persisted over 8 years after BMT and were able to proliferate in the presence of mitogens and of some antigens, although to a lesser extent than control T cells. A stop mutation was identified which predicts that the major part of the cytoplasmic tail of gamma c is truncated. This mutation does not affect high-affinity IL-2 binding, but it partly decreases IL- 2 endocytosis and prevents the downmodulation of the IL-2-receptor beta chain and the tyrosine phosphorylation of Jak 3 protein in response to IL-2. This report raises questions concerning the role of the gamma c chain in IL-2 receptor endocytosis and in T-cell development and differentiation.
Involvement of P-glycoprotein in the transmembrane transport of interleukin-2 (IL-2), IL-4, and interferon-gamma in normal human T lymphocytes
Authors: Drach J , Gsur A , Hamilton G , Zhao S , Angerler J , Fiegl M , Zojer N , Raderer M , Haberl I , Andreeff M , Huber H 
Published: October 2019

Abstract
The physiological role of the multidrug resistance P-glycoprotein (P- gp), which is expressed by normal human T lymphocytes, is still largely unknown. To investigate whether or not P-gp is involved in the transport of cytokines, peripheral blood lymphocytes were stimulated with phytohemagglutinin (PHA) in the absence or presence of P-gp inhibitors, and concentrations of cytokines (interleukin-2 [IL-2], IL- 4, IL-6, interferon-gamma [IFN-gamma]) in the supernatants of these cultures were quantitated by enzyme-linked immunosorbent assay. P-gp inhibitors included verapamil (Ver), tamoxifen (Tmx), and the P-gp specific monoclonal antibody UIC2. Release of IL-2 was significantly suppressed by these inhibitors at concentrations that were also effective in blocking efflux of Rhodamine-123 from normal T lymphocytes. IL-2 mRNA expression in lymphocytes was not different between PHA control and the cultures with P-gp inhibitors. Ver and Tmx did not interfere with T-cell activation as determined by CD25 and CD69 expression. In a nonhematological model, the P-gp expressing HCT-8 adenocarcinoma cell line, exogenously added IL-2 was shown to exert an inhibitory effect on P-gp mediated Rhodamine-123 efflux. In addition, transepithelial transport of IL-2 by electrophysiologically tight and polarized HCT-8 monolayers was examined. A time-dependent flux of IL-2 across dense monolayers, which was partially inhibited by Ver, was observed. We also investigated whether or not P-gp inhibitors suppressed release of other cytokines produced by activated T cells (IL- 4, IL-6, IFN-gamma). Release of IL-4 and IFN-gamma was significantly inhibited by Ver, Tmx, and UIC2; however, release of IL-6 remained unaffected. These data show P-gp mediated transmembrane flux of IL-2 in T lymphocytes and HCT-8 cells. We conclude that P-gp participates in the transport of cytokines (IL-2, IL-4, and IFN-gamma) in normal peripheral T lymphocytes.
Oligonucleotide uptake in human hematopoietic cells is increased in leukemia and is related to cellular activation
Authors: Zhao Q , Song X , Waldschmidt T , Fisher E , Krieg AM 
Published: October 2019

Abstract
The use of antisense oligonucleotides as tools for modulating gene expression represents a novel strategy for designing drugs to treat a variety of diseases. Several factors, including cellular uptake and internalization of the oligonucleotides, are important parameters in determining the effectiveness of antisense agents such as therapeutic drugs. We have studied oligonucleotides uptake in normal and leukemic human hematopoietic cells, such as peripheral blood, bone marrow (BM), and HL-60 cell line; and have found that, in normal human blood and BM, myeloid cells and B cells preferably took up more oligonucleotides than T cells. There was no marked difference in oligonucleotide uptake between CD4+ helper T cells and CD8+ cytolytic T cells. Leukemic cells had greater oligonucleotide uptake than their normal counterparts. Furthermore, oligonucleotide uptake was closely related to cell activation status and can be modulated by growth factors or inhibitors. These studies provide a basis for using oligonucleotides as therapeutic drugs both in vitro and in vivo.
Upregulated expression of BCL-2 in multiple myeloma cells induced by exposure to doxorubicin, etoposide, and hydrogen peroxide
Authors: Tu Y , Xu FH , Liu J , Vescio R , Berenson J , Fady C , Lichtenstein A 
Published: October 2019

Abstract
Enhanced expression of the antiapoptotic gene BCL-2 may participate in chemoresistance. To ascertain if multiple myeloma cells surviving exposure to chemotherapy alter their BCL-2 expression, we treated the myeloma cell lines 8226, IM-9, and U266 as well as a primary myeloma cell culture with various injurious agents. Doxorubicin, etoposide, and hydrogen peroxide consistently induced a concentration- and time- dependent upregulation of BCL-2 expression in all myeloma target cell types assayed by flow cytometry and Western blot analysis. In contrast, serum starvation, dexamethasone, and anti-fas antibodies had no effect on expression. Enhanced expression of BCL-2 was relatively selective as treatments had no effect on expression of Ig light chains, BCL-X, or actin. An reverse transcriptase-polymerase chain reaction assay showed increased levels of BCL-2 RNA in 8226 cells as early as 4 hours after treatment with doxorubicin at a time when cell recoveries were not decreased. Thus, doxorubicin stimulates BCL-2 expression in individual 8226 cells rather than simply allowing a selected survival of high BCL- 2-expressing cells in culture. Doxorubicin-treated 8226 cells with upregulated BCL-2 expression were relatively resistant to a second exposure of doxorubicin. In addition, BCL-2-transfected IM-9 cells, with enhanced expression of BCL-2 which was comparable to that achieved by initial exposure to doxorubicin, were resistant to doxorubicin and etoposide cytotoxicity. These data suggest that exposure to chemotherapeutic agents may enhance BCL-2 expression in surviving myeloma cells and contribute to acquired chemoresistance.
Establishment and characterization of a novel acute promyelocytic leukemia cell line (UF-1) with retinoic acid-resistant features
Authors: Kizaki M , Matsushita H , Takayama N , Muto A , Ueno H , Awaya N , Kawai Y , Asou H , Kamada N , Ikeda Y 
Published: October 2019

Abstract
All-trans retinoic acid (RA) induces complete remission in a high proportion of patients with acute promyelocytic leukemia (APL). Nevertheless, most of these patients develop RA resistance and relapse. The mechanisms of RA resistance by APL cells are still unclear. To understand the characteristics of human leukemia, human leukemic cell lines are useful tools for study. APL cells have a strikingly low proliferation potential in vitro; thus, only one APL cell line has been established. We developed a novel APL cell line (UF-1) from a patient clinically resistant to all-trans RA. Cell surface markers in the UF-1 cells were positive for CD7, CD13, CD33, and CD38. Cytogenetic analyses revealed additional abnormalities, 46XX, add(1)(q44), add(6)(q12), add(7)(q36), t(15;17) (q21;q21). Molecular analyses showed a PML/RAR alpha fusion transcript. Sequence analysis of the RAR alpha gene in RA- resistant HL-60 cells disclosed a point mutation in codon 411 (C to T substitution), whereas UF-1 cells showed the normal sequence. All-trans RA did not change morphological features of the cell, NBT reduction activity, or their expression of CD11b antigens as determined by FACS analysis except at 10(-6) mol/L. RA also did not alter the growth curve of the cells as determined by the MTT assay. These findings suggest that the UF-1 cell is the first permanent cell line with spontaneous RA- resistant APL cells. This RA-resistant APL cell line may be a useful model for molecular studies on the block of leukemic cell differentiation and as a means to investigate the mechanisms of RA resistance.
ABO glycosyltransferase genotyping by polymerase chain reaction using sequence-specific primers
Authors: Gassner C , Schmarda A , Nussbaumer W , Schonitzer D 
Published: October 2019

Abstract
Serological typing for the classical ABO blood groups is routinely performed using anti-A and anti-B antisera of polyclonal or monoclonal origin, which are able to distinguish four phenotypes (A, B, AB, and O). Modern molecular biology methods offer the possibility of direct ABO genotyping without the need for family investigations. Typing can be done with small amounts of DNA and without detection of blood group molecules on the surface of red blood cells. We developed a system of eight polymerase chain reactions (PCR) to detect specific nucleotide sequence differences between the ABO alleles O1, O2, A1, A2, and B. PCR amplification using sequence-specific primers and detection of amplification products by agarose gel electrophoresis is one of the fastest genotyping methods and is easy to handle. With our method we tested the A1,2BO1,2 genotypes of 300 randomly chosen persons out of a pool of platelet donors and found the results to be consistent with ABO glycosyltransferase phenotypes. We also identified a presumably new ABO allele, which may be the result of a crossing-over event between alleles O1 and A2.
Enhancement of thymopoiesis after bone marrow transplant by in vivo interleukin-7
Authors: Bolotin E , Smogorzewska M , Smith S , Widmer M , Weinberg K 
Published: October 2019

Abstract
Bone marrow transplantation (BMT) is followed by a period of profound immune deficiency, during which new T lymphocytes are generated from either stem cells or immature thymic progenitors. Interleukin-7 (IL-7) induces proliferation and differentiation of immature thymocytes. We examined whether the in vivo administration of IL-7 to mice receiving BMT would alter thymic reconstitution. Lethally irradiated C57BL/6 mice received syngeneic BMT, followed by either IL-7 or placebo from days 5 to 18 post-BMT. At day 28, BMT recipients that had not received IL-7 had profound thymic hypoplasia (< 5% of normal), with relative increases in the numbers of immature thymocytes, decreased numbers of mature peripheral (splenic) T lymphocytes, and severely impaired T- and B-cell function. In contrast, transplanted mice treated with IL-7 had normalization of thymic cellularity, with normal proportions of thymic subsets and T-cell receptor beta variable gene (TCRV beta) usage, normal numbers of peripheral CD4+ T lymphocytes, and improved antigen- specific T- and B-cell function. In the BMT-IL-7 mice, there was an eightfold increase in the number of immature CD3-CD4-CD8- thymocytes in G2-M of the cell cycle, indicating that restoration of thymic cellularity was due to enhanced proliferation of immature thymic progenitors. Similar effects following IL-7 administration were also observed when donor bone marrow was depleted of mature T lymphocytes, indicating that IL-7 administration affected immature hematopoietic progenitors. IL-7 promotes thymic reconstitution after BMT, and may be useful in preventing post-BMT immune deficiency.
Deletions and Loss of Expression of P16INK4a and P21Waf1 Genes Are Associated With Aggressive Variants of Mantle Cell Lymphomas
Authors: Pinyol Magda , Hernandez Luis , Cazorla Maite , Balbı́n Milagros , Jares Pedro , Fernandez Pedro L. , Montserrat Emilio , Cardesa Antonio , Lopez-Otı́n Carlos , Campo Elı́as 
Published: October 2019

Abstract
Mantle cell lymphoma (MCL) is molecularly characterized by bcl-1 rearrangement and cyclin D1 gene overexpression. Some aggressive variants of MCL have been described with blastic or large cell morphology, higher proliferative activity, and shorter survival. The cyclin-dependent kinase inhibitors (CDKIs) p21Waf1 and p16INK4a have been suggested as candidates for tumor-suppressor genes. To determine the role of p21Waf1 and p16INK4a gene alterations in MCLs, we examined the expression, deletions, and mutations of these genes in a series of 24 MCLs, 18 typical, and 6 aggressive variants. Loss of expression and/or deletions of p21Waf1 and p16INK4a genes were detected in 4 (67%) aggressive MCLs but in none of the typical variants. Two aggressive MCLs showed a loss of p16INK4a expression. These cases showed homozygous deletions of p16INK4a gene by Southern blot analysis. An additional aggressive MCL in which expression could not be examined showed a hemizygous 9p12 deletion. Loss of p21Waf1 expression at both protein and mRNA levels was detected in an additional aggressive MCL. No p21Waf1 gene deletions or mutations were found in this case. The p21Waf1 expression in MCLs was independent of p53 mutations. The two cases with p53 mutations showed p21Waf1 and p16INK4a expression whereas the 4 aggressive MCLs with p16INK4a and p21Waf1 gene alterations had a wild-type p53. p21Waf1 and p16INK4a were expressed at mRNA and protein levels in all typical MCLs examined. No gene deletions or point mutations were found in typical variants. Two typical MCLs showed an anomalous single-stranded conformation polymorphism corresponding to the known polymorphisms at codon 148 of p16INK4a gene and codon 31 of p21Waf1 gene. These findings indicate that p21Waf1 and p16INK4a alterations are rare in typical MCLs but the loss of p21Waf1 and p16INK4a expression, and deletions of p16INK4a gene are associated with aggressive variants of MCLs, and they occur in a subset of tumors with a wild-type p53 gene.