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Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome resulting from a reciprocal translocation between chromosomes 9 and 22 [t9;22] that gives rise to a BCR::ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase in developed countries. Tyrosine kinase inhibitor (TKI) therapy is a highly effective treatment option for patients with chronic phase-CML. The primary goal of TKI therapy in patients with chronic phase-CML is to prevent disease progression to accelerated phase-CML or blast phase-CML. Discontinuation of TKI therapy with careful monitoring is feasible in selected patients. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase-CML.

Double minute chromosomes (DMs), although relatively frequently encountered in solid tumors, are rare in hematologic neoplasms such as acute myeloid leukemia (AML), and even rarer in lymphoid neoplasms. t(3;3)(q26.2;q21) is a very rare genetic alteration observed in myeloid neoplasm. Herein we report an interesting and unique case of concomitant C-MYC DMs and t(14;18)-containing large B-cell lymphoma, which was successfully treated with R-hyper-CVAD; unfortunately, the patient has developed a therapy-related AML (t-AML) 2 years since the start of his lymphoma treatment. His t-AML contains both t(3;3)(q26.2;q21) and monosomy 7, and the patient died of AML 10 months after the initial diagnosis of t-AML despite clinical remission. To the best of our knowledge, this is the first reported case of C-MYC DM-containing de novo large B-cell lymphoma, which was successfully treated with complete remission, but unfortunately died of t-AML harboring t(3;3)(q21;q26)., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

This study aimed to determine the quality of information available on the internet regarding Total Hip Replacement (THR). The unique websites identified were categorised by type and assessed using the DISCERN score, the Journal of the American Medical Association (JAMA) benchmark criteria, and a novel (THR)-specific content score. The presence of the Health On the Net (HON) code, a reported quality assurance marker, was noted. Commercial websites predominate. Governmental & Non-Profit Organizations websites attained the highest DISCERN score. Sites that bore the HONcode seal obtained significantly higher DISCERN and THR content scores than those without the certification. Physicians should recommend the HONcode seal to their patients as a reliable indicator of website quality or, better yet, refer patients to sites they have personally reviewed., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Despite prophylaxis with immunosuppressive agents or a variety of other approaches, many patients suffer from acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation. Although consensus has emerged supporting the use of high-dose methylprednisolone or prednisone for initial treatment of aGVHD, practices differ among centers with respect to the initial glucocorticoid dose, the use of additional immunosuppressive agents, and the approach to withdrawal of treatment after initial improvement. Despite many studies, practices vary considerably with respect to the selection of agents for treatment of glucocorticoid-resistant or refractory GVHD. Investigators and clinicians have recognized the lack of progress and lamented the absence of an accepted standard of care for secondary treatment of aGVHD. The American Society of Blood and Marrow Transplantation has developed recommendations for treatment of aGVHD to be considered by care providers, based on a comprehensive and critical review of published reports. Because the literature provides little basis for a definitive guideline, this review also provides a framework for the interpretation of previous results and the design of future studies., (Copyright © 2012 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)

The patient is a 45-year-old woman with a history of breast cancer who had been treated 1 year ago with radiation and chemotherapy. Flow cytometric analysis of bone marrow aspirate revealed 81% blasts positive for CD4, CD11c (partial), CD13, CD19 (partial), cytoplasmic CD22, CD34, CD36, CD45, cytoplasmic CD79a, CD117 (partial), HLA-DR, and terminal deoxynucleotide transferase, consistent with a mixed phenotype acute leukemia (B/myeloid lineage). Conventional karyotypic analysis revealed a t(4;22)(q12;q11.2) in 12 of 13 cells analyzed. Fluorescence in situ hybridization analysis using a dual-color, dual-fusion break cluster region/ABL probe set showed no break cluster region/ABL translocation but an extra break cluster region signal in 85% (170/200) of cells, consistent with a translocation involving the break cluster region gene at 22q11.2. A FIP1L1/CHIC2/platelet-derived growth factor receptor α deletion/fusion probe showed signal separation in 96.5% (193/200) of interphase nuclei. Reverse transcriptase-polymerase chain reaction using sense break cluster region primers and an antisense platelet-derived growth factor receptor α primer resulted in a product of approximately 590 base pairs, consistent with the presence of a break cluster region/platelet-derived growth factor receptor α fusion gene. Because of the presumptive platelet-derived growth factor receptor α translocation and its sensitivity to tyrosine-kinase inhibitor, the patient was treated with imatinib mesylate, cytarabine, and idarubicin as induction and maintenance therapy; and she has remained free of disease for 5 months since the initial diagnosis., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Allogeneic hematopoietic cell transplantation (HCT) is the only curative strategy for patients with myelodysplastic syndrome (MDS) and myeloproliferative disorders (MPD). We report the results of 148 patients (median age = 59 years old) with de novo MDS (n = 40), acute myelogenous leukemia (AML) after antecedent MDS/MPD (n = 49), treatment-related MDS (t-MDS) (n = 25), MPD (n = 27), and chronic myelomonocytic leukemia (CMML) (n = 7) who underwent allogeneic HCT using a conditioning regimen of low-dose total body irradiation (TBI) alone (200 cGy) on day 0 (n = 5) or with the addition of fludarabine (Flu) 30 mg/m(2)/day on days -4 to -2 (n = 143). Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil (MMF). Seventy-five patients (51%) received an allograft from a matched related donor (MRD), and 73 patients (49%) were recipients of unrelated donor (URD) grafts. There was no significant difference in the incidence of acute (gr II-IV) and chronic extensive graft-versus-host disease (aGVHD, cGVHD) between the recipients of related and unrelated donor grafts. By day +28, 75% of patients demonstrated mixed T cell chimerism. Graft rejection was seen in 15% of patients. With a median follow-up of 47 (range: 6-89) months, the 3-year relapse-free survival (RFS) and overall survival (OS) are both 27% for all patients, with a relapse incidence of 41%. The 3-year RFS for the patients with de novo MDS, AML after antecedent MDS/MPD, t-MDS, MPD, and CMML were 22%, 20%, 29%, 37%, and 43%, respectively, and the 3-year OS was 20%, 23%, 27%, 43%, and 43%, respectively. The 3-year nonrelapse mortality (NRM) was 32%. Factors associated with a lower risk of relapse were the development of extensive cGVHD and having a low risk or intermediate-1 risk International Prognostic Score for the de novo MDS patients. Nonmyeloablative HCT confers remissions in patients who otherwise were not eligible for conventional HCT but for whom relapse is the leading cause of treatment failure.

Lenalidomide is approved for red blood cell (RBC) transfusion-dependent anemia due to low or intermediate-1 (int-1) risk myelodysplastic syndromes (MDSs) associated with a chromosome 5q deletion with or without additional cytogenetic abnormalities. We report results of a multicenter, phase 2 trial evaluating lenalidomide therapy for transfusion-dependent patients with low- or int-1-risk MDS without deletion 5q. Eligible patients had 50,000/mm(3) or more platelets and required 2 U or more RBCs within the previous 8 weeks; 214 patients received 10 mg oral lenalidomide daily or 10 mg on days 1 to 21 of a 28-day cycle. The most common grade 3/4 adverse events were neutropenia (30%) and thrombocytopenia (25%). Using an intention-to-treat analysis, 56 (26%) patients achieved transfusion independence (TI) after a median of 4.8 weeks of treatment with a median duration of TI of 41.0 weeks. In patients who achieved TI, the median rise in hemoglobin was 32 g/L (3.2 g/dL; range, 10-98 g/L [1.0-9.8 g/dL]) from baseline. A 50% or greater reduction in transfusion requirement occurred in 37 additional patients, yielding a 43% overall rate of hematologic improvement (TI response + ||>or= 50% reduction in transfusion requirement). Lenalidomide has clinically meaningful activity in transfusion-dependent patients with low- or int-1-risk MDS who lack the deletion 5q karyotypic abnormality.

Tandutinib (MLN518/CT53518) is a novel quinazoline-based inhibitor of the type III receptor tyrosine kinases: FMS-like tyrosine kinase 3 (FLT3), platelet-derived growth factor receptor (PDGFR), and KIT. Because of the correlation between FLT3 internal tandem duplication (ITD) mutations and poor prognosis in acute myelogenous leukemia (AML), we conducted a phase 1 trial of tandutinib in 40 patients with either AML or high-risk myelodysplastic syndrome (MDS). Tandutinib was given orally in doses ranging from 50 mg to 700 mg twice daily The principal dose-limiting toxicity (DLT) of tandutinib was reversible generalized muscular weakness, fatigue, or both, occurring at doses of 525 mg and 700 mg twice daily. Tandutinib's pharmacokinetics were characterized by slow elimination, with achievement of steady-state plasma concentrations requiring greater than 1 week of dosing. Western blotting showed that tandutinib inhibited phosphorylation of FLT3 in circulating leukemic blasts. Eight patients had FLT3-ITD mutations; 5 of these were evaluable for assessment of tandutinib's antileukemic effect. Two of the 5 patients, treated at 525 mg and 700 mg twice daily, showed evidence of antileukemic activity, with decreases in both peripheral and bone marrow blasts. Tandutinib at the MTD (525 mg twice daily) should be evaluated more extensively in patients with AML with FLT3-ITD mutations to better define its antileukemic activity.

Pulmonary leukostasis is a rare but serious and often fatal complication of chronic myeloid leukemia (CML) in blast crisis and acute myeloid leukemia. Treatment options are limited for these patients. Imatinib mesylate (STI-571, Gleevec, Novartis) is a potent and selective inhibitor of the BCR-abl tyrosine kinase, the molecular abnormality that causes CML. The case of a 74-year-old man with a history of CML who presented in myeloid blast crisis with pulmonary leukostasis characterized by increasing dyspnea, hypoxemia, fever, and impending respiratory failure is reported. The patient was treated with single agent imatinib mesylate (IM) with rapid decrease in his white blood cell count (WBC) and marked improvement in his respiratory status. No electrolyte abnormalities consistent with tumor lysis syndrome were observed. IM may be an effective single agent therapy for pulmonary leukostasis in patients with CML blast crisis who are at the risk for tumor lysis.

Isolated central nervous system (CNS) relapse occurred in 5 out of 24 patients (20.8%) with chronic myeloid leukemia (CML) lymphoid blast crisis (2), Philadelphia (Ph) chromosome positive acute lymphoblastic leukemia (ALL) (2) or CML with biphenotypic markers (1) treated on imatinib mesylate (IM) protocols at our institution. CNS relapse occurred despite peripheral blood (5) and bone marrow (3) complete responses. Median time to CNS relapse was day 32 (range 23 to 100). This observation raised the possibility that IM may not penetrate into the CNS. Simultaneous plasma and cerebral spinal fluid (CSF) IM levels were determined in four subsequent patients by liquid chromatography and mass spectrophotometric assay. Levels of IM were found to be approximately two logs lower in CSF than in plasma (0.044 microg/ml (0.088 +/- 0.029 micrro) vs 3.27 microg/ml (6.54 +/- 0.93 microM)). CSF levels were substantially below the concentration required for inhibition of BCR-ABL and killing of cell lines in vitro. These results suggest that IM may not penetrate the intact blood/brain barrier and its implications are discussed.

Erythropoietin (Epo) autocrine stimulation has been implicated in erythroleukemia. To develop a model of Epo autocrine stimulation, we made transgenic mice using a construct that linked the human Epo gene to an erythroid-specific regulatory element, designated 5'HS-2, from the human beta-globin locus control region. We hypothesized that Epo gene expression would be targeted to erythroid cells in these mice, resulting in autocrine stimulation of erythroid progenitor cell growth in culture, and that chronic autocrine Epo stimulation would result in erythroleukemia. Transgenic mice containing intact copies of the 5'HS-2Epo construction had elevated hematocrits, reticulocyte counts and serum Epo levels and marked splenic enlargement. Analysis of RNA isolated from organs of transgenic mice revealed constitutive Epo mRNA expression primarily in spleen, blood and bone marrow. RNA samples from anemic transgenic mice revealed Epo gene induction only in the liver. Marrow derived from 5'HS-2Epo mice grew BFU-E in the absence of exogenous Epo. Despite observation of up to 2 years, no mouse developed erythroleukemia, demonstrating that Epo autocrine stimulation alone is insufficient for progression to malignancy. These studies show that 5'HS-2 can be used to target Epo gene expression to erythroid tissue. These mice could provide a model system for studying autocrine growth regulation.

We collected human immunodeficiency virus (HIV) disease progression, survival, most recent CD4 cell count, and plasma HIV RNA levels from patients (n=157) who participated in randomized clinical trials of interleukin (IL)-2 that commenced before 1995. Data were available for 155 (99%) patients. Statistical analyses were based on the intention-to-treat principle. Median follow-up was 28 months and 30 months for control and IL-2 patients, respectively. Twenty-five (16%) patients developed AIDS or died during follow-up (16 control patients vs. 9 IL-2 patients; R2=0.57; P=.22). Mean change from baseline CD4 cell count was significantly higher in patients randomized to receive IL-2 (368 vs. 153 cells/microL; P=.003). Mean change from baseline plasma HIV RNA was significantly lower in patients randomized to receive IL-2 (-0.98 vs. -0.63 log copies/mL; P=.004). Significant improvements in CD4 cell count and plasma HIV RNA in recipients of IL-2 relative to control patients were associated with a nonsignificant trend toward improved clinical outcome.

Human erythropoietin (Epo) gene expression is inducible by hypoxia or anaemia in the kidney and liver. Previous transgenic mouse experiments have demonstrated that sequences required for Epo gene induction in the kidney reside in a 7 8 kb Barn HI fragment located 6 kb upstream of the gene. To sublocalize these sequences, we performed Desoxyribonuclease I (DNAse I) mapping studies using transgenic mice which carried this DNA fragment. These studies revealed a DNAse I hypersensitive site (DNAse I HS) located 4 6 kb from the upstream end of the 7.8 kb fragment in anaemic kidney and liver samples. Sequence analysis of the region encompassing the DNAse I HS revealed an element with remarkable homology to the 3' Epo gene hypoxia-inducible enhancer. This suggested the presence of an additional regulatory element that contributes to the control of hypoxia-inducible Epo gene expression in kidney and liver. We constructed transgenic mice containing the human Epo gene linked to either the 5 kb upstream or 2.5 kb downstream portion of the 7.8kb fragment. Inducible expression was limited to the liver. Thus, neither fragment was alone sufficient to confer kidney inducible expression. These findings indicate that sequences more than 8.5 kb upstream of the Epo gene are required for kidney-specific induction. They suggest that either those sequences reside in an 0.3 kb Hind III fragment located between the 5 kb and the 2.5 kb fragments or that sequences in the 5 kb or 0.3 kb fragments must interact with sequences in the 2.5 kb fragment to allow Epo gene induction in the kidney.

Erythropoietin (Epo) gene expression in kidney and liver is inducible by anemia. To localize the sequences necessary for regulated expression of the Epo gene, we constructed transgenic mice containing five human Epo gene constructs and examined Epo expression under basal conditions and with anemia. Mice containing the Epo gene with 0.3 kb of 5' flanking sequence, 0.7 kb of 3' flanking sequence, and either all introns or only intron I alone were polycythemic, had Epo expression in various tissues (including non-Epo-producing tissues), and induction only in liver. In contrast, mice containing the Epo gene with 8.5 kb of 3' flanking sequence and either 9.5 or 22 kb of 5' flanking sequence had basal expression at low levels in appropriate tissues and were less likely to be markedly polycythemic. Mice with the smaller of these two constructs had induction only in the liver, whereas those with the larger construct had induction in the kidney and liver. These studies indicate that sequences sufficient for induction in the liver are located in close proximity to the Epo gene, including the immediate 5' and 3' flanking sequence and the first intron. They also indicate that sequences required for induction in the kidney are located more than 9.5 kb 5' to the gene. Furthermore, comparison of these and prior transgenic studies suggest that sequences that limit the basal expression of the Epo gene are located downstream of the gene. We conclude that multiple cis DNA sequences are required for regulated Epo gene expression.

Erythropoietin (Epo) synthesis increases in response to hypoxia. The hepatoma cell line Hep 3B produces low basal levels of Epo mRNA which increase markedly with hypoxia. To define the sequences necessary for this response, we linked fragments of the human Epo gene to a luciferase vector, introduced these plasmids into Hep 3B cells and assayed for luciferase activity after growth in 1% or 21% oxygen. A 621-bp Epo promoter fragment resulted in a 2.4-fold increase in luciferase activity with hypoxia. We tested several Epo gene fragments upstream of this Epo promoter fragment and found that a 613-bp Bgl II-Pvu II 3' fragment had a 10-fold increase in activity with hypoxia regardless of orientation. This fragment had a similar level of activity when linked to a simian virus 40 promoter. Portions of this fragment retained activity, including a 38-bp Apa I-Taq I fragment that had a 17-fold increase in activity with hypoxia. Deletion of nt 4-13 or 19-28 from this 38-bp fragment resulted in a loss of activity. The 24-bp upstream portion of the 38-bp fragment showed an 8-fold increase in activity with hypoxia. However, deletion of nt 19-24 or mutagenesis of nt 21 or 22 in this 24-bp fragment resulted in loss of activity. Our studies indicate that the transcriptional response of the human Epo gene to hypoxia is mediated in part by promoter sequences and to a greater degree by an enhancer element located in a 24-bp portion of the 3' flanking sequence of the gene.

The beta-globin locus control region (LCR) consists of four erythroid-specific DNase I-hypersensitive sites, which are necessary for high-level expression of the beta-like globin genes in erythroid tissues. One of these sites, designated 5'HS-2, functions as an erythroid-specific enhancer element in transfection and transgenic mouse experiments. Recent transfection experiments and studies of DNA-protein interactions have localized the 5'HS-2 enhancer to 18 nucleotides that contain a binding site for both the erythroid-specific factor nuclear factor erythroid 2 (NFE-2) and for activator protein 1 (AP-1). To define the sequences necessary for in vivo enhancer activity, several deletion mutants of 5'HS-2 were linked to the human beta-globin gene and their activity was tested in transgenic mice. Three upstream fragments of 5'HS-2 [341, 374, and 412 base pairs (bp)], each of which contained the NFE-2/AP-1 sequences, resulted in beta-globin expression at levels equivalent to or higher than those observed with the entire 732-bp 5'HS-2 fragment. In contrast, a 358-bp downstream portion of 5'HS-2, which lacked the NFE-2/AP-1 sequences, resulted in beta-globin expression at the low levels seen with the beta-globin gene alone. Removal of the NFE-2/AP-1 sequences by a 67-bp internal deletion resulted in similar low levels of beta-globin expression. A 100-bp 5' fragment that contained the NFE-2/AP-1 sequences resulted in beta-globin expression that was higher than the beta-globin gene alone but lower than the entire 5'HS-2 fragment or the three larger upstream fragments. These studies demonstrate that the NFE-2/AP-1 sequences are essential for enhancer activity of 5'HS-2 but that other sequences are required for full activity in vivo.

We have previously described an English family with gamma delta beta-thalassemia in which a large deletion stops 25 kilobases (kb) upstream from the beta-globin gene locus, and yet the beta-globin gene is inactive in vivo. Affected family members had a beta-thalassemia minor phenotype with a normal hemoglobin A2 level. Gene mapping showed that these subjects were heterozygous for a chromosome bearing a large deletion that began in the G gamma-globin gene, extended through the epsilon-globin gene, and continued upstream for at least 75 kb. The A gamma-, delta-, and beta-globin gene loci on this chromosome were intact. To examine the possibility that an additional defect was present in the beta-globin gene, we cloned, sequenced, and examined the expression of the beta-globin gene from the affected chromosome. No mutation was found in the beta-globin gene sequence from 990 base-pairs 5' to the cap site to 350 basepairs 3' to the polyadenylation signal. The gene was subcloned into an expression vector and introduced into HeLa cells. Analysis of RNA derived from these cells, using a ribonuclease protection assay, revealed qualitatively and quantitatively normal transcription. Thus a structurally and functionally normal beta-globin gene is inactive in the presence of a large deletion more than 25 kb upstream. The loss of beta-globin gene function may be due to disturbance of chromatin conformation caused by the deletion or may be the result of loss of upstream sequences that are necessary for beta-globin gene expression in vivo.

Several lines of evidence suggest that erythroid-specific DNase I hypersensitive sites (HS) located far upstream of the human beta-globin gene are important in regulating beta-globin gene expression. We used the polymerase chain reaction technique to amplify and clone an 882-base-pair DNA fragment spanning one of these HS, designated HSII, which is located 54 kilobases upstream of the beta-globin gene. The cloned HSII fragment was linked to a human beta-globin gene in either the genomic (HSII-beta) or antigenomic (HSII-beta) orientation. These two constructs and a beta-globin gene alone (beta) were injected into fertilized mouse eggs, and expression was analyzed in liver and brain from day-16 transgenic fetuses. Five of 7 beta-transgenic fetuses expressed human beta-globin mRNA, but the level of expression per gene copy was low, ranging from 0.93 to 22.4% of mouse alpha-globin mRNA (average 9.9%). In contrast, 11 of 12 HSII-beta transgenic fetuses expressed beta-globin mRNA at levels per gene copy ranging from 31.3 to 336.6% of mouse alpha-globin mRNA (average 139.5%). Only three fetuses containing intact copies of the HSII-beta construct were produced. Two of three expressed human beta-globin mRNA at levels per gene copy of 179.2 and 387.1%. Expression of human beta-globin mRNA was tissue-specific in all three types of transgenic fetuses. These studies demonstrate that a small DNA fragment containing a single erythroid-specific HS can stimulate high-level human beta-globin gene expression in transgenic mice.