bluuebunny/crossref_metadata_2025_split huggingface dataset:
The CXCR4 Antagonist, AMD3100, Inhibits AML Transmigratory Activity but Does Not Alter Blast Proliferation or Survival.
Authors: Liesveld Jane L. , Lancet Jeffrey E. , Rosell Karen E. , Bechelli Jeremy , Abboud Camille N. , Phillips Gordon L. 
Published: April 2020

Abstract
Stromal cell derived factor-1 (SDF-1α) and its receptor, CXCR4 play a role in the trafficking of CD34+ cells. AMD3100, a selective CXCR4 antagonist, can mobilize hematopoietic progenitors from marrow to peripheral blood in healthy human volunteers and in patients with multiple myeloma and non-Hodgkin’s lymphoma (Flomenberg et al, Blood 102, 39a, 2003). Overexpression of CXCR4 on human CD34+ progenitors increases their proliferation and NOD/SCID repopulating capacity (Kahn et al. Blood 103:2942, 2004). Since CXCR4 has been found to regulate the migration and development of AML stem cells in NOD/SCID mice, we studied the effect of AMD3100 on AML cells from the standpoint of proliferation and in vitro transendothelial transmigration utilizing a transwell system. AMD3100 (from AnorMED, Inc.), at concentrations from 0.1 to 1.0 ng/ml did not affect the viability or porliferation of purified AML blasts (n=4). AMD3100 did not influence the adherence of AML blasts to endothelial monolayers. In the presence of 0.1 to 1 ng/ml AMD-3100, the transmigration of normal CD34+ cells stimulated by 100 ng/ml SDF-1α through a human umbilical vein endothelial cell (HUVEC) monolayer was completely inhibited. Likewise, the transmigration of AML blasts through HUVECs was not altered by AMD3100 exposure, but the SDF-1α mediated transmigration was inhibited by AMD3100 from 0.1 to 1 ng/ml. The same effect was noted with AML transmigration through marrow stromal layers. The increase in transmigration through endothelial cells stimulated with G-CSF was not inhibited by AMD3100 whereas the transmigration stimulated by interleukin-8 was inhibited. When AMD3100 was placed in the bottom of the migration chamber, no independent effects on AML transmigration were noted. Co-culture of AML blasts with stromal monolayers protected blasts from apoptosis. This protection was not altered by SDF-1α, AMD3100, nor by the combination. These in vitro results demonstrate that AMD3100 can influence the migratory capacity of AML cells but has no direct effects on their proliferation or survival. Further in vitro and in vivo studies will be required to elucidate the role that this unique chemokine antagonist has in the mobilization potential of AML blasts or progenitors or in the interactions of AML cells with their microenvironment. Such studies have implications for AML autografting and AML blast interactions with extramedullary endothelial cells.
Williams-Beuren Syndrome Critical Region-5/Non-T Cell Activation Linker: A Novel Target Gene of AML1/ETO.
Authors: Lübbert Michael , Stock Michael , Berg Tobias , Fliegauf Manfred 
Published: April 2020

Abstract
The chromosomal translocation (8;21) fuses the AML1 gene on chromosome 21 and the ETO gene on chromosome 8 in human acute myeloid leukemias, resulting in expression of the chimeric transcription factor AML1/ETO. AML1/ETO-mediated dysregulation of target genes critical for hematopoietic differentiation and proliferation is thought to contribute to the leukemic phenotype. Several mechanisms, including recruitment of histone deacetylases (HDACs) to AML1 target genes, may be responsible for altered gene expression. We used an ecdysone-inducible expression system in the human monoblastic U-937 cell line to isolate genes that were differentially expressed upon induction of AML1/ETO expression. By representational difference analysis (cDNA-RDA), we identified 26 genes whose expression levels were significantly modulated following AML1/ETO induction for 48 hours. None of these genes has previously been described as a target of AML1, ETO or AML1/ETO. One gene down-regulated by AML1/ETO in vitro, Williams Beuren Syndrome critical region 5 (WBSCR5), was expressed in primary t(8;21) negative AML blasts but not in primary t(8;21) positive AML blasts, strongly implying a role of this gene in the phenotype of t(8;21) positive AML. WBSCR5 is part of the critical region located on chromosome 7q11.23 that is deleted in the Williams Beuren syndrome (OMIM 194050), an autosomal dominant disorder comprising vascular, neurological, behavioral and skeletal abnormalities. WBSCR5 has recently been shown to have a role in the activation and differentiation of B cells (Brdicka et al., J. Exp. Med. 196:1617, 2002) and thus was also termed Non-T cell activation linker.. WBSCR5 as well as seven other regulated genes were further studied using all-trans-retinoic acid (ATRA), an inducer of differentiation of U-937 cells, and Trichostatin A (TSA), an HDAC inhibitor. WBSCR5 and two other out of these eight genes were regulated during ATRA-induced monocytic differentiation of U-937 cells, however none of them antagonistically, upon both ATRA-treatment and AML1/ETO-induction. Since repression of WBSCR5 might be mediated by recruitment of HDACs through the fusion gene, cells were treated with TSA prior to transgene induction. However, the AML1/ETO-associated dysregulation of WBSCR5 gene expression (as well as that of the other seven genes studied) was not mediated by a TSA-sensitive mechanism. The identified genes provide a useful model to study the mechanism by which the AML1/ETO fusion protein exerts its function in transcriptional dysregulation in acute myeloid leukemia. The role of WBSCR5 in malignant hematopoietic cells warrants further study.
Expression of Erythropoietin and Erythropoietin Receptor in Squamous Cell Carcinomas of the Head and Neck: Levels of Erythropoietin Expression Correlate with Tumor Hypoxia.
Authors: Arcasoy Murat O. , Amin Khalid , Chou Shu-Chuan , Haroon Zishan A. , Varia Mahesh , Raleigh James A. 
Published: April 2020

Abstract
Erythropoietin (EPO), an oxygen-regulated glycoprotein hormone, is a hematopoietic cytokine that stimulates erythropoiesis by binding to its cellular receptor EPOR. The recombinant form of human EPO is widely used in clinical practice for the prevention or treatment of anemia associated with cancer and chemo-radiation therapy. However, in a recent randomized, placebo-controlled trial involving patients receiving curative radiotherapy for squamous cell carcinoma of the head and neck, EPO treatment was associated with poorer loco-regional progression-free survival. The purpose of this study was to determine whether EPOR and its ligand EPO are expressed in primary squamous cell carcinomas of the head and neck. We also investigated the hypothesis that EPO expression in malignant cells may be associated with the presence of tumor hypoxia, an important factor involved in resistance to radiation treatment, tumor aggressiveness and poor prognosis. Twenty-one patients with squamous cell carcinoma of the head and neck were enrolled in a tumor hypoxia study under a research protocol approved by the Institutional Review Board at the University of North Carolina Hospitals. All patients provided signed informed consent. The patients received an intravenous infusion of the hypoxia marker pimonidazole hydrochloride (Hypoxyprobe-1™) prior to multiple tumor biopsies. Two or more biopsies were available from all except one primary tumor. The tissue specimen from one patient with laryngeal carcinoma was excluded because of availability of only a single, small and fragmented biopsy. Contiguous sections from 74 biopsies were analyzed by immunohistochemistry for expression of EPOR and EPO as well as pimonidazole binding. We found EPOR expression in tumor cells in 97% of the biopsies. The pattern of EPOR immunoreactivity was predominantly cytoplasmic but was found to be localized to the membrane in some sections. Co-expression of EPO was observed in 90% of biopsies. Qualitative and semi-quantitative analyes for EPO staining and tumor hypoxia on a section-by-section basis revealed that EPO and pimonidazole adduct staining did not always co-localize within tumors but there was a significant positive correlation between levels of micro-regional EPO expression and pimonidazole binding (r = 0.736, P &lt; 0.001, n=20 by two-tailed Spearman’s rank correlation analysis). These data demonstrate the co-expression of EPOR and its ligand EPO in squamous carcinoma cells suggesting that EPO may play a novel role as a potential autocrine or paracrine growth factor in head and neck cancer. Furthermore, EPO expression in tumor cells may be modulated, at least in part, by tumor hypoxia. The expression of EPOR needs to be taken into consideration in the design of future clinical trials investigating the role of recombinant human EPO in head and neck cancer.
Time Interval from Last Chemotherapy to Stem Cell Collection Correlates with Peripheral Blood Absolute Lymphocyte Count at Apheresis and Survival Post-Autologous Stem Cell Transplantation in Non-Hodgkin’s Lymphoma.
Authors: Holtan Shernan G. , Porrata Luis F. , Inwards David J. , Ansell Stephen A. , Micallef Ivana N.M. , Litzow Mark R. , Gertz Morie A. , Lacy Martha Q. , Dispenzieri Angela , Gastineau Dennis A. , Tefferi Ayalew , Elliott Michelle , Hogan William J. , Hayman Suzanne , Markovic Svetomir N. 
Published: April 2020

Abstract
The infused autograft absolute lymphocyte count (A-ALC) is an independent prognostic factor for survival after autologous hematopoietic stem cell transplant (AHSCT) in non-Hodgkin’s lymphoma (NHL). Previous studies have shown that A-ALC directly correlates with the peripheral blood absolute lymphocyte count (PC-ALC) at the time of apheresis collection. However, factors affecting the PC-ALC at apheresis remain undefined. We hypothesized that one possible factor impacting PC-ALC may be the time interval from last chemotherapy to stem cell collection (TILC). Data from 160 patients who underwent AHSCT for treatment of relapsed NHL at Mayo Clinic between 1993 and 2001 were collected and analyzed. The primary end point of this study was correlation between TILC and PC-ALC, and our analysis revealed a strong correlation (r = 0.67, p &lt; 0.0001). Further analysis revealed higher PC-ALC numbers in patients with TILC ≥ 60 days versus TILC &lt; 60 days (median of 7.44 x 109/L in the ≥ 60 day group versus 3.87 x 109/L in the &lt; 60 day group, p &lt; 0.0001). Both the median overall survival (figure below) and the progression-free survival were longer in the TILC ≥ 60 days group versus the TILC &lt; 60 days group (76 versus 21 months, p &lt; 0.0037; 76 versus 11 months, p &lt; 0.018, respectively). These findings were independent of other prognostic indicators for relapsed NHL patients undergoing APHSCT. The data supports our hypothesis that TILC affects PC-ALC and survival post-AHSCT in NHL.
Figure Figure
More Than One Mutation Is Required for Leukemia Development Following Retroviral Vector-Mediated Gene Transfer.
Authors: Kustikova Olga , Schmidt Manfred , Modlich Ute , Li Zhixiong , Schmidt Sonja , Deichmann Anette , Rudolph Cornelia , von Neuhoff Nils , Schlegelberger Brigitte , Fehse Boris , Kalle Christof , Baum Christopher 
Published: April 2020

Abstract
As recent case reports have suggested that proto-oncogene activation by replication-deficient retroviral vectors may trigger leukemia in mice and men, there is an urgent need for models allowing predictive investigations into the pathomechanisms of this complication. Previously, we have shown that dose-escalated replication-defective retrovirus vectors (such as HaMDR1 or SF91dsRedpre) may trigger combinatorial leukemia-initiating events in single cells, with a probability that allows prospective studies in simple mouse models (C57Bl/6). Meanwhile, we have performed molecular analyses for 5 different leukemias, harboring 6 to 12 vector insertions according to Southern blot. 34 insertions recovered from these clones by LM-PCR and LAM-PCR showed that 4 leukemias had combinatorial hits in at least one established proto-oncogene (class 1 genes: Hivep1, Mllt3, Fli1, HoxA7, Brd2, Evi1, Csfr3, Bcl11a, Ski) with at least one hit in other signaling genes (class 2 genes). One leukemia for which 2 insertions remain to be identified showed at least 3 class 2 hits, so far without a class 1 event. All leukemias presented with hits in genes involved in cytoplasmic signal cascades along with genes contributing to nuclear regulatory networks. Some of these leukemias had a normal karyotype. A comparison with 62 insertion sites from healthy control animals (determined in peripheral blood DNA harvested 7 months after transplantation) revealed a significant enrichment of class 1 hits in leukemias (14-fold over expected and 3-fold over control). Healthy animals still showed 6 hits (~10%) in class 1 genes, obviously not being sufficient for leukemia induction. Three of these occurred upstream of Evi1, one upstream of Nfic, one upstream of Pdclg2, and one in Bcl11a. Interestingly, upstream vector insertion was preferred in class 1 gene hits. Overall, insertions recovered from both normal and leukemic samples revealed an overrepresentation of hits within (or upstream of) known or predicted genes (89 and 90%, respectively). In line with the data of a related murine marking study (Kustikova, Fehse et al., ASH 2004), our study strongly suggests that single hits in class 1 or class 2 genes are not sufficient to induce leukemia in mice. However, certain combinations of such events in single cells may well be leukemogenic with a given latency. Our findings establish a powerful approach for both oncogene discovery and safety validation in gene therapy.
BCR/ABL→STAT5 Pathway Stimulates Helix-Loop-Helix Id-1 Protein To Enhance the MMP9 - Dependent Invasiveness of Leukemia Cells.
Authors: Nieborowska-Skorska Margaret , Hoser Grazyna , Malecki Maciej , Wasik Mariusz , Skorski Tomasz 
Published: April 2020

Abstract
BCR/ABL oncogenic tyrosine kinase activates STAT5, which plays as important role in leukemogenesis (Nieborowska-Skorska et al., J.Exp.Med., 189:1229,1999). We reported before that the bcl-2 family member A1 and the proto-oncogene pim-1, the two downstream effectors of STAT5, collaborate in BCR/ABL-positive cells to induce protection from apoptosis and growth factor independence (Nieborowska-Skorska et al., Blood, 99:4531,2002). We show here that expression of the helix-loop-helix protein Id1 is enhanced by BCR/ABL in the STAT5-dependent manner. This effect requires activation of STAT5 by the signaling from SH3+SH2 domains of BCR/ABL. Enhanced expression of Id1 played a key role in the BCR/ABL-mediated cell invasion in vitro, but not in protection from apoptosis in the absence of growth factors and in promotion of growth factor-independent proliferation. Leukemogenesis in mice was prolonged after injection of BCR/ABL-positive cells, in which Id-1 was downregulated by the antisence cDNA. In addition, infiltration of central nervous system (CNS) by leukemia cells was also reduced if Id-1 was inhibited. Id1 was responsible for BCR/ABL-induced production of MMP9 metalloproteinase. Abrogation of MMP9 catalytic activity by a selective inhibitor or blocking antibody decreased the invasive capability of leukemia cells. These data indicate that BCR/ABL→STAT5→Id1→MMP9 pathway may play a critical role in the BCR/ABL-dependent leukemogenesis by regulation of the invasive capability of leukemia cells. Moreover, this pathway may protect CML cells from imatinib mesylate (IM) by facilitation of their localization in CNS, a sanctuary for leukemia cells during IM therapy.
Tumor-Derived Chaperone-Rich Cell Lysate (CRCL) Can Be Effectively Combined with Syngeneic Bone Marrow Transplantation to Treat Bcr-abl+ Leukemia in a Murine Model.
Authors: Chen Xinchun , Zeng Yi , Li Gang , Thompson Sylvia , Sepassi Marjan , Romanoski M. Angela , Graner Michael W. , Katsanis Emmanuel 
Published: April 2020

Abstract
We have previously reported that purified tumor derived chaperone-rich cell lysate (CRCL) containing multiple heat shock proteins (HSPs) is a promising cancer vaccine, capable of generating tumor-specific T cell responses and protective immunity in different animal tumor models. In this study, we have explored the therapeutic applicability of CRCL in the context of syngeneic bone marrow transplantation (BMT) to treat preexisting leukemia. BALB/c mice received a 10-fold LD100 dose of bcr-abl+ leukemia cells (12B1) subcutaneously (s.c.) on day -7. On day -1, 900cGy of total body irradiation (TBI) was given followed by syngeneic bone marrow transplantation (BMT) on day 0. Transplanted mice received 20X106 bone marrow cells along with 50X106 splenocytes (SPC) intravenously (i.v.). We have demonstrated that BMT/SPC prolonged survival of mice by a median time of 7 days (median survival time [MST] from tumor inoculation of no BMT versus BMT/SPC =19 vs 26 days), however, all mice eventually died of disseminated leukemia. When recipients received BMT and SPC from syngeneic donors that had been previously immunized with 12B1-derived CRCL (immune BMT/SPC) the MST was increased to 29 days with 26.1% of transplanted mice surviving without tumor (p&lt;0.01 immune BMT/SPC vs naive BMT/SPC). Vaccination of immune BMT/SPC recipients with 20 mg 12B1-derived CRCL in the early post-transplant period (day +1 and day +6) increased MST to 32 days (p&lt;0.01 vs naïve BMT/SPC control) but did not significantly improve overall survival (26.3%) when compared to immune BMT/SPC mice not receiving post transplant 12B1-CRCL vaccine. Eleven to 17 weeks later, mice with no evidence of disease were re-challenged with 12B1 cells in one groin and A20 B cell leukemia cells in the opposite groin. Eighty percent of the mice demonstrated long term tumor specific immunity by rejecting the 12B1 rechallenge while 100% of the mice developed A20 tumors. Our results indicate that CRCL is a promising vaccine that can be used to generate specific anti-tumor immunity that can be effectively transferred to a host via BMT.
Mitochondrial Mutations as Molecular Markers for Minimal Reidual Disease (MRD) in Acute Myeloid Leukemia.
Authors: Morley Alexander A. , Grist Scott A. , Lu Xiao J. , Patsouris Katrina 
Published: April 2020

Abstract
Measurement of minimal residual disease (MRD) is being increasingly used in haematological malignancies in order to assess prognosis and decide on treatment. However for some patients, including many patients with acute myeloid leukemia (AML), molecular techniques for MRD measurement cannot be performed owing to lack of a molecular marker. We have detected mitochondrial mutations (MM) in the D loop of the mitochondrial genome of the leukemic cells in approximately 40% of patients with AML and have investigated 2 techniques - denaturing gradient gel electrophoresis (DGGE) and single nucleotide primer extension (SNUPE) - to detect and quantify them. Mixing experiments showed that DGGE had a sensitivity of approximately 0.5% for detection of MM, and it was able to detect leukemia in remission marrow in 5 of 6 patients with AML. When present in a patient, MM are usually multiple. We therefore tested a 2-step strategy, as shown in the figure, which involved initial enrichment by PCR using primers directed at 1 or 2 flanking mutations followed by DGGE to detect an inner mutation. In 2 mixing experiments this 2-step strategy increased sensitivity of detection down to 0.0001% (this level of detection was evident in the original gel photo).
Figure Figure
SNUPE was more sensitive than DGGE and in 3 mixing experiments it showed a sensitivity of 0.02–0.05%. Four patients with AML have now been studied by SNUPE and the levels of MRD in the marrow documenting morphological remission at the end of induction therapy were 2.8%,16.1%,40.8% and 15.7%. The relatively high levels of MRD as measured by PCR in 3 patients suggest that some of the leukaemic cells at the end of induction may be more mature than blasts and thus not identifiable by morphology. While questions remain to be answered, mitochondrial mutations are promising molecular markers for quantifying MRD in AML and possibly other haematological disorders
Mutations in the Receptor Tyrosine Kinase Pathway Are Associated with Clinical Outcome in Patients with Acute Myeloblastic Leukemia Harboring t(8;21)(q22;q22).
Authors: Nanri Tomoko , Matsuno Naofumi , Kawakita Toshiro , Suzushima Hitoshi , Kawano Fumio , Mitsuya Hiroaki , Asou Norio 
Published: April 2020

Abstract
AML1-MTG8 generated by t(8;21)(q22;q22) contributes to leukemic transformation but additional events are required for full leukemogenesis. We examined whether mutations in the receptor tyrosine kinase (RTK) pathway could be the genetic events that cause acute myeloblastic leukemia (AML) harboring t(8;21). Mutations in the second tyrosine kinase domain, juxtamembrane domain and exon 8 of the C-KIT gene were observed in 7, 1 and 3 of 37 AML patients with t(8;21), respectively. Three patients showed an internal tandem duplication in the juxtamembrane domain of the FLT3 gene. One patient had a mutation in the K-Ras gene at codon 12. As the occurrence of these mutations was mutually exclusive, a total of 15 (41%) patients showed mutations in the RTK pathway. These results suggest that AML1-MTG8 predisposes cells to the acquisition of activating mutations in the RTK pathway as an additional event leading to the development of AML. Ten of 15 patients with mutations in the RTK pathway relapsed, compared with only 3 of 19 patients lacking such mutations (p=0.0042). Furthermore, the 6-year disease-free survival (DFS) in patients with mutations was 12% compared to 55% in those without mutations (p=0.0344). When patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) were censored at the date of the HSCT, patients with mutations had a 6-year DFS of 0% versus 60% for the patients without mutations (p=0.0096) These observations indicate that RTK mutations are associated with the clinical outcome in t(8;21) AML.