bluuebunny/crossref_metadata_2025_split huggingface dataset:
Donor-Cell Acute Leukemia after Sibling Marrow Grafting for Aplastic Anemia: Another Type of Familial Monosomy 7?.
Authors: Benattar Laurence K. , Bouffard Laurence , Coignet Lionel J. 
Published: April 2020

Abstract
We report here the case of a bone marrow transplant (BMT) patient who received a graft from her 1-year-old HLA-identical brother for severe aplastic anemia (AA) with severe thrombopenia at the age of 4, followed by myelodysplasia at the age of 6 that transformed to AREBt/AML type M6 at the age of 7. She died at the age of 8.
Two years after the BMT, the brother developed hypoplasia that rapidly transformed to AML-M2 and he died rapidly during chemotherapy induction.
Cytogenetic results showed that the brother initially developed an AML-M2 with a t(16;21) translocation and, 3 years later, the patient developed an AREBt/AML-M6 with a monosomy 7 and a donor profile (45,XY,−7). Retrospective examinations did not allow the detection of the t(16;21) in any samples of the patient nor monosomy 7 in any available sample from her brother.
This observation shows that the same cells (the donor cells) in another microenvironment, even HLA-identical, can transform to different acute leukemia types with different chromosomal abnormalities. In both, the chromosomal abnormalities seem to appear at a late stage of the disease and can be considered a secondary event. Familial MDS/AML with monosomy 7 are well described: heterozygous deletion and nonpreferential deletion of parental chromosome suggest that the inherited gene(s) might not be located on chromosome 7. Other familial hematological disorders such as familial platelet disorders present a AML1 translocation or mutation. In our case, on one hand, two hematological disorders in siblings (one AA and one AML at diagnosis) can be considered a familial case even if the past medical history of the other members of the family is unremarkable. On the other hand, the same cells (the brother’s cells) have provided a translocation involving AML1 in the donor and a monosomy 7 in the recipient, the two genetic abnormalities being involved in familial hematological disorders. We could hypothesize that those two events might have been induced by the same inherited gene(s) that could be responsible at the same time for familial monosomy 7 and for other familial hematological disorders.
Proteomics Analysis of Bone Marrow Cells of Acute Myeloid Leukemia (M2a) and Its Prognosis Significance.
Authors: Meng Fan Yi , Tian Shuai , Tang Jia-ming 
Published: April 2020

Abstract
Objective:The distinct proteins of leukemic cells were investigated by proteomics technology between AML-M2a patients before inductive treatments with evidently different duration of first continuous complete remission(CCR1) and AML-M2a patients at replase in order to find their relations with prognosis of AML-M2a.
Methods:The bone marrow mononuclear cells(BMMNCs) from 17 cases of AML-M2a patients before inductive treatment were grouped with different duration of CCR1: group A with CCR1 duration exceeded 12 months(11 cases), group B within 6 months(6 cases), and group C was composed of 3 patients at replase among group B. The proteins of BMMNCs from all the patients were separated by two-dimensional electrophoresis, and the part of differentially-expressed proteins were identified by matrix assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS).
Results: 6 differentially-expressed proteins were identified between group A and B by MALDI-TOF-MS: tubulin-specific chaperone B, myeloperoxidase, &lt;TT&gt;Solution Structure Of The Ch Domain Of Human Transgelin-2,&lt;/TT&gt; glutathione S-transferase, RING zinc finger protein, glyceraldehyde-3-phosphate dehydrogenase.3 differentially-expressed proteins were identified in group C: NAD(P)H dehydrogenase, hypothetical protein, HES1.
Conclusion: The distinct proteins of leukemic cells of AML-M2a patients before inductive treatments were involved in prognosis, and the proteins of BMMNCs from patients at replase have changed.
Livin Expression in Normal Hematopoietic Cells and in Hematologic Malignancies.
Authors: Abd-Elrahman Ihab , Bucholtz Vered , Hershko Klilah , Amir Gail , Perlman Riki , Ben-Yehuda Dina 
Published: April 2020

Abstract
Livin is a member of the Inhibitor of Apoptosis Proteins (IAP) family, a novel family of intracellular anti-apoptotic proteins that act by binding and inhibiting caspases. We found that Livin is unique among the IAP members as upon strong apoptotic stimuli, it is specifically cleaved by caspases to produce a large C-terminal subunit. This subunit has a paradoxical pro-apoptotic activity. Thus, Livin is not merely an inhibitor of apoptosis. Rather, it is a regulator of apoptosis that can protect against apoptosis but upon continuous apoptotic signals it helps to assure cell death. We showed that Livin plays a major role in melanoma. The level of the Livin protein is directly correlated to the resistance of melanoma cells to chemotherapy and to the survival rate of melanoma patients. Livin was also shown to be over expressed in other solid tumors such as nasopharyngeal, neuroblastoma, colorectal and lung cancers. In this work we studied Livin expression in normal hematopoietic cells as well as hematologic malignancies. Using immunohistochemistry staining for Livin we evaluated its expression in reactive lymph nodes (LN) and showed that in contrast to Bcl2, Livin was detected in highly proliferating germinal centers. In normal bone marrow Livin was detected in Megakaryocytes and immature myeloid precursors. In peripheral blood mononuclear cells, using quantitative RT-PCR, we found that Livin expression was down regulated in activated monocytes and T cells while in B cells, Livin was upregulated upon activation. We studied bone marrow and LNs from 84 patients (pts) with hematologic malignancies. Positive immunohistochemistry staining was found in the malignant cells of all pts with DLBC NHL (31 pts), follicular lymphoma (12 pts) and multiple myeloma (15 pts). Peripheral blood samples from 28 B-CLL pts were compared with healthy controls’ B cells. High mRNA levels were detected in 43% of the pts, in correlation with older age (p&lt;0.05). On the other hand, Livin was not expressed in Hodgkin’s disease (4 pts and 4 cell lines) and only 6/29 pts with AML had high levels of Livin in RT-PCR without any clinical correlation. Our data demonstrate that Livin is over expressed in activated normal B cells both in peripheral blood and LN as well as in most B cell lymphoproliferative diseases. Further investigation will establish the role of Livin over expression in hematologic malignancies.
Upregulation of SOCS-1 and Downregulation of miR-214 Correlate with Disease Course in Chronic Lymphocytic Leukemia.
Authors: Jones Kimberly A. , Phillips John D. , Mendell Joshua T. , Glenn Martha G. , Yu Margaret K. 
Published: April 2020

Abstract
SOCS-1, suppressor of cytokine signaling, is a negative regulator of the JAK2/STAT signal transduction pathway. This pathway, often deregulated in myeloproliferative disorders, has not yet been implicated in chronic lymphocytic leukemia (CLL). We demonstrated SOCS-1 upregulation and miR-214 downregulation with clinical response in a patient treated with cladribine. Similar changes were not seen in a treated patient with progressive disease. MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate expression of other genes by complementary pairing at the seed sequence in the 3′-UTR of the target mRNA. Some patients with CLL reportedly regulate bcl-2 expression by downregulating miR-15a and miR-16-1. Although no experimentally verified targets have been demonstrated for miR-214, complete inhibition of miR-214 by anti-sense inhibitors prevents apoptosis in Hela cells. Of the 44 predicted human miRNAs that target SOCS-1 (http://microrna.sanger.ac.uk), we determined the expression of 24 of these by real-time PCR using the Early Access Human Panel from Applied Biosystems. MiR-214 was the only downregulated miRNA after treatment. The other 23 miRNAs were either upregulated or unchanged. We demonstrated SOCS-1 protein upregulation by two fold after cladribine in the “responsive” patient without a concomitant increase in the transcript level as measured by real time PCR. SOCS-1 expression is often silenced by DNA promoter methylation in hematologic and solid tumor malignancies. We report another mechanism of regulation through miRNA translational repression. This suggests involvement of the JAK2/STAT pathway in B-cell survival in CLL.
Aberrant Transcriptional Regulation of the MLL Fusion Partner EEN Gene by AML1-ETO and Its Implication in Leukemogenesis.
Authors: Ma Li-Heng , Liu Han , Xiong Hui , Chen Bing , Fang Yi , Zhang Xiao-Mei , Wang Yue-Ying , Huang Qiu-Hua , Zhang Qing-Hua , Li Bo-Liang , Chen Zhu , Chen Sai-Juan 
Published: April 2020

Abstract
EEN (extra eleven nineteen) gene located on chromosome 19p13 was cloned as a fusion with MLL from an acute myeloid leukemia (AML) patient with translocation t(11;19)(q23;p13). In this study, we characterized the genomic structure of EEN gene including its 5′ regulatory region and transcription start site (TSS). We found that Sp1 could bind to the GC-stretch of EEN promoter and was critical for the normal EEN expression, while the leukemia associated fusion protein AML1-ETO could aberrantly transactivate EEN gene through an AML1 binding site. Of note, overexpressed EEN showed oncogenic properties, such as transforming potential in NIH3T3 cells, stimulating cell proliferation and increasing the activity of transcriptional factor AP-1. Retroviral transduction of EEN increased self-renewal and proliferation of murine hematopoietic progenitor cells. Moreover, Kasumi-1 and HL60 cell growth was inhibited with down regulation of EEN by RNAi. These findings demonstrate that EEN might be a common target in two major types of AML associated with MLL or AML1 translocations, and over-expression of EEN may play an essential role in leukemogenesis.
TGFβ Activates p53 Via PP2A in Hematopoietic Cells.
Authors: Takimoto Rishu , Kato Junji , Takada Koichi , Takahari Daisuke , Niitsu Yoshiro 
Published: April 2020

Abstract
Dysfunction of TGFβ signal transduction has been shown to result in leukemogenesis. It has been generally accepted that Smads mediate the TGFβ signaling to inhibit cell proliferation, while several Smad4-impaired cell lines retain certain levels of responsiveness to TGFβ, suggesting an additional TGFβ signaling pathway for cell cycle arrest. Here we demonstrate evidence for a novel signal pathway for G1 arrest linking TGFβ and p53/Protein phosphatase 2A (PP2A) in CD4+ T lymphocyte and megakaryocytes. TGFβ induced growth suppression, associated with increment of PP2A activity was clearly observed in cells with impaired Smad signal. In these cells, upon TGFβ stimulation, PP2A was transiently recruited by heteromeric complex of TGFβ receptors (TβRs), released into cytosol, and activated. Subsequently, PP2A dephosphorylated p53 to import it into nucleus by interacting with importin-α/β followed by p21Waf1 induction. The recruitment of PP2A by TβRs and TGFβ-induced growth suppression as well as nuclear import of p53 were inhibited by introduction of siRNA for PP2A-Bα. Based on these preliminary observation, we next used human peripheral CD4+ T lymphocytes, which are reportedly impaired in Smad signaling, but sensitive to TGFβ when stimulated with PHA and IL-2. Growth suppression induced by TGFβ was almost completely abolished by siRNA for p53 (siRNA-p53), but not by siRNA for Smad4 (siRNA-Smad4). Further, nuclear translocation of p53 was inhibited by siRNA for PP2A-Bα(siRNA-Bα). These results suggest that growth suppressive activity of TGFβ in certain immunological responses could be ascribed to PP2A/p53 signal transduction. Thus these results define a novel pathway of TGFβ-induced growth suppression linking p53-PP2A, and suggest that loss of function of p53 which is frequently observed in hematological malignancies may result in the escape from growth inhibitory signal of TGFβ.
Significance of Ubiquitin Ligase Subunit SKP-2 Proto-Oncogene and Proliferative Marker Ki67 Expression in Diffuse Large B-Cell Lymphoma.
Authors: Uddin Shahab , Hussain Azhar R. , Bavi Prashant P. , Al-Kuraya Khawla S. 
Published: April 2020

Abstract
S-phase kinase-associated protein 2 (SKP-2) is a proto-oncogene that has been shown to be expressed in a number of tumors. A number of studies have shown that SKP-2 plays a role in the degradation of tumor suppressor genes by increased proteosome-dependent degradation. SKP-2 overexpression is highly representative of intrinsic biological aggressiveness of certain cancers including breast, non-small cell lung cancer and gastric carcinoma, how ever its role in hematological malignancies have not yet been explored. Therefore, in this study we examined 100 clinical samples of diffuse large B-cell lymphoma (DLBCL) to study the expression pattern of ubiquitin ligase subunit SKP-2 proto-oncogenes and its relation to proliferative index marker protein Ki67 to correlate tumor aggressiveness. The expression of SKP-2 and Ki67 were examined by immunohistochemistry using specific antibodies on formalin-embedded tissue sections of DLBCL patients. Our data showed that SKP-2 was over expressed in majority of DLBCL and was associated with expression pattern of the proliferating index marker Ki67 protein. Since increased proteosome-dependent degradation of tumor suppressor genes play a critical role in the etiology of various tumors and proteosome inhibition is a novel approach for treating malignancies and has been approved for clinical use, we sought to determine whether inhibition of proteosome by MG132, a specific proteosome inhibitor induces apoptosis in a panel of DLBCL cell lines. Our data showed that treatment of DLBCL cell lines by MG132 induced apoptosis in a dose dependent manner. Inhibition of proteosome also decreased the expression of SKP-2 leading to subsequent disruption of mitochondrial membrane potential causing release of cytochrome c into the cytosol. Release of cytochrome c resulted in activation of caspase-3 and cleavage of PARP ultimately leading to apoptosis. These data suggests that SKP-2 expression plays a major role in the oncogenesis of DLBCL and overexpression of SKP-2 can be used as useful prognostic marker. Furthermore, proteosome inhibitors can be used as future therapeutic modality in treating DLBCL.
A Cell-Free Assay To Screen for Compounds That Modulate the Fanconi/BRCA Pathway.
Authors: Stone Stacie , Sobeck Alexandra , Landais Igor , LaChapelle Alexis , Hoatlin Maureen E. 
Published: April 2020

Abstract
Fanconi anemia is a multi-gene cancer susceptibility and bone marrow failure syndrome. In the current model, at least eight proteins (FANCA, -B-C,-E, -F, -G, -L, -M) are part of a nuclear complex that is required for the S phase and DNA-damage dependent monoubiquitination of FANCD2. This event is thought to functionally link the FA complex proteins to major breast cancer susceptibility proteins BRCA1, BRCA2 (FANCD1), and the BRCA1-associated helicase Brip1(FANCJ). An understanding of the function of the FA protein network is incomplete not only because some FA proteins are still unidentified, but also because the functions of individual proteins may be interdependent and are difficult to assess out of context with the entire FA network. We recently developed a cell-free system to evaluate the function of the Fanconi/BRCA pathway proteins in an S phase context in Xenopus egg extracts (Sobeck, et al. 2006). Egg extracts are naturally cell-cycle synchronized and mimic the complex interplay of proteins that support cellular DNA replication and regulated DNA damage checkpoint activation. Intricate protein interactions can be assayed in egg extracts, even without knowing each of the components if there is a measurable endpoint. We tested the hypothesis that the mobility shift of FANCD2 could be used as an endpoint in cell-free assays to determine FA pathway function. We found that an antibody specific for the Xenopus FANCD2 protein detected a single band of the expected size in western blots of proteins separated by SDS-PAGE from unstimulated egg extracts. Addition of DNA substrates to extracts resulted in the appearance of a slower mobility form of FANCD2, consistent with the monoubiquitinated FANCD2-L isoform observed in human cells following DNA damage. We measured inhibition or stimulation of xFANCD2-L in the presence of a series of candidate compounds.
We found compounds that inhibit FANCD2-L, including curcumin, which was also identified in a cell-based assay as an inhibitor of FANCD2-L (Chirnomas, et al., 2006). Thus, this cell-free assay successfully mirrors the outcome obtained with a small molecule inhibitor of the FA/BRCA pathway in cell-based assays. This new approach is an improvement relative to cell-based screens because the extracts are fully synchronized, which maximizes the sensitivity of detection of S-phase events. Moreover, cell-free screens are rapid, inexpensive and well suited for semi- or high-throughput methods to identify small molecules that modulate the FA/BRCA DNA-damage response pathway.
Anaplastic Lymphoma Kinase Is Activated through the Pleiotrophin/Receptor Protein Tyrosine Phosphatase (RPTP)β/ζ Signaling Pathway: A Unique Mechanism of Activation of Receptor Protein Tyrosine Kinases.
Authors: Perez-Pinera Pablo , Zhang Wei , Wang Zhaoyi , Berenson James R. , Deuel Thomas F. 
Published: April 2020

Abstract
Anaplastic Lymphoma Kinase (ALK) is a receptor-type transmembrane tyrosine kinase (RTK) of the insulin receptor superfamily that structurally is most closely related to leukocyte tyrosine kinase. It was first discovered as a chimeric protein (NPM-ALK) of nucleophosmin and the C-terminal (kinase) domain of ALK in anaplastic large cell lymphomas (ALCL). NPM-ALK is constitutively active and generates the oncogenic signals that are the pathogenic mechanisms of these highly malignant cancers. The full-length ALK also is believed to have an important role in the pathogenesis of other human malignancies, since its expression is found in rhabdomyosarcomas, neuroblastomas, neuroectodermal tumors, glioblastomas, breast carcinomas, and melanomas. Recently it was proposed that pleiotrophin (PTN the protein, Ptn the gene) is the ligand that stimulates ALK to transduce signals to activate downstream targets. However, this proposal contrasted with earlier studies that demonstrated Receptor Protein Tyrosine Phosphatase (RPTP)β/ζ is the functional receptor for PTN. PTN was shown to inactivate RPTPβ/ζ and thereby permit the activity of different tyrosine kinases to increase tyrosine phosphorylation of the substrates of RPTPβ/ζ at the sites that are dephosphorylated by RPTPβ/ζ in cells not stimulated by PTN. Subsequent studies identified β-catenin, β-adducin, Fyn, GIT1/Cat-1, P190RhoGAP, and histone deacetylase 2 (HDAC-2) as downstream targets of the PTN/RPTPβ/ζ signaling pathway and demonstrated that their levels of tyrosine phosphorylation increase in PTN-stimulated cells. This diversity of PTN-regulated targets is one basis for the pleiotrophic activities of PTN. We now demonstrate that tyrosine phosphorylation of ALK is increased in PTN-stimulated cells through the PTN/RPTPβ/ζ signaling pathway. It is furthermore shown that ALK is activated in PTN-stimulated cells when it is expressed in cells without its extracellular domain, that β-catenin is a substrate of ALK, that the tyrosine phosphorylation site in β-catenin phosphorylated by ALK is the same site dephosphorylated by RPTPβ/ζ, and that PTN-stimulated tyrosine phosphorylation of β-catenin requires expression of ALK. The data suggest a unique mechanism to activate ALK; the data support a mechanism in which β-catenin is phosphorylated in tyrosine through the coordinated inactivation of RPTPβ/ζ, the activation of the tyrosine kinase activity of ALK, and the phosphorylation of β-catenin by ALK at the same site regulated by RPTPβ/ζ in PTN-stimulated cells. Since PTN often is inappropriately expressed in the same malignancies that express ALK, the data suggest a mechanism through which ALK signaling may contribute to those malignancies that express full length ALK through the activity of PTN to signal constitutively the same pathways as NPM-ALK in ALCL.
Identification of Chemotherapy-Resistant Mechanisms in Childhood T-ALL Cell Lines: Correlation with Genetic Profiles in Patients Having Early Treatment Failure.
Authors: Estes David A. , Lovato Debbie M. , Khawaja Hadya M. , Winter Stuart S. , Larson Richard S. 
Published: April 2020

Abstract
Acquisition of drug resistance in childhood T-cell acute lymphoblastic leukemia (T-ALL) is a major cause of treatment failure. Drug resistant cell lines are effective tools for elucidating mechanisms of acquired drug resistance. In this study, we developed novel drug resistant cell lines that could be employed to identify mechanisms of drug resistance. We established three new drug resistant T-ALL cell lines: 2 resistant to L-asparaginase (L-asp), and one resistant to daunorubicin (DNR). The DNR-resistant line (Jurkat) acquired a 117-fold increase in EC50 to DNR, from 20.6 nM to 2.4 μM, while the L-asp resistant cells (Jurkat and Sup T1) showed respective increases in resistance of 320-fold (0.003 IU/mL to 0.962 IU/mL) and 29-fold (0.042 IU/mL to 1.22 IU/mL). The DNR resistant cell line acquired a multidrug resistant phenotype, showing 310 and 120-fold increase in resistance to vincristine and prednisolone, respectively. Resistance to L-asp was unchanged. Microarray analysis showed that ABCB1 (MDR1, P-glycoprotein) was significantly upregulated (567-fold) in DNR resistant cells. siRNA experiments that reduced ABCB1 mRNA levels by 74% restored DNR sensitivity. In L-asp resistant T-ALL cells (Jurkat and Sup T1), two notable genes were upregulated, asparagine synthetase (ASNS) which catalyzes synthesis of asparagine (41-fold and 1.5-fold) and argininosuccinate synthase (ASS)(32-fold and 6.5-fold), respectively. Reduction of ASNS with siRNA restored drug sensitivity in both cell lines. Interestingly, siRNA suppression of ASS in conjunction with ASNS achieved an exaggerated restoration of drug sensitivity compared to ASNS alone. We next examined the microarray profiles of drug resistant cells with those of 86 T-ALL patients; of which 8 failed induction (IF). Interestingly, these 3 key genes are upregulated in 25–62% of IF cases. Although ABCB1 overexpression has been shown to be a mechanism of DNR resistance in many cancers, there is a paucity of resistant T-ALL cell lines to adequately model the effect of stage of differentiation and genetic heterogeneity underlying drug resistance in T-ALL. With the establishment of 3 new T-ALL cell lines in this report, there exist 5 T-ALL drug resistant cell lines, representing the spectrum of T-cell differentiation (pre-T, cortical T, and mature T cells). Finally, this is the first report of the potential contribution of ASS in addition to ASNS to L-asp resistance in leukemia cells.