ABSTRACT
BACKGROUND: Autologous haematopoietic stem cell transplantation (AHSCT) is an effective treatment for patients with multiple sclerosis (MS) who have highly active disease, despite the use of standard disease-modifying therapies (DMTs). However, the optimal time for offering AHSCT to patients with 'aggressive' MS is yet to be established. OBJECTIVES: The objective was to explore the safety and efficacy of AHSCT as a first-line DMT in patients with 'aggressive' MS. METHODS: All patients with 'aggressive' MS who received AHSCT as a first-line DMT in five European and North American centres were retrospectively evaluated. RESULTS: Twenty patients were identified. The median interval between diagnosis and AHSCT was 5 (1-20) months. All had multiple poor prognostic markers with a median pre-transplant Expanded Disability Status Scale (EDSS) score of 5.0 (1.5-9.5). After a median follow-up of 30 (12-118) months, the median EDSS score improved to 2.0 (0-6.5, p < 0.0001). No patient had further relapses. Three had residual magnetic resonance imaging (MRI) disease activities in the first 6 months post-transplant, but no further new or enhancing lesions were observed in subsequent scans. CONCLUSION: AHSCT is safe and effective as a first-line DMT in inducing rapid and sustained remission in patients with 'aggressive' MS.
Subject(s)
Hematopoietic Stem Cell Transplantation , Multiple Sclerosis , Humans , Multiple Sclerosis/therapy , Retrospective Studies , Transplantation, Autologous , Treatment OutcomeSubject(s)
COVID-19 Drug Treatment , Dexamethasone/administration & dosage , Diabetes Mellitus/drug therapy , Diabetes Mellitus/epidemiology , Glycemic Control/methods , SARS-CoV-2 , COVID-19/epidemiology , Comorbidity , Dexamethasone/adverse effects , Humans , Hypoglycemia/chemically induced , Hypoglycemia/prevention & control , Insulin, Isophane/administration & dosageABSTRACT
Introduction: Cyclophosphamide-bortezomib-dexamethasone (CyBorD) is considered a standard induction regimen for transplant-eligible patients with newly diagnosed multiple myeloma (mm). It has not been prospectively compared with bortezomib-dexamethasone (Bor-Dex). We aimed to compare the efficacy of CyBorD and Bor-Dex induction in transplant-eligible patients. Methods: In a retrospective observational study at a single tertiary centre, all patients with transplant-eligible mm who received induction with CyBorD or Bor-Dex between March 2008 and April 2016 were enrolled. Progression-free survival (pfs), response, and stem-cell collection for a first autologous stem-cell transplantation (ahsct) were compared. Results: Of 155 patients enrolled, 78 (50.3%) had received CyBorD, and 77 (49.7%), Bor-Dex. The patients in the Bor-Dex cohort were younger than those in the CyBorD cohort (median: 57 years vs. 62 years; p = 0.0002) and more likely to have had treatment held, reduced, or discontinued (26% vs. 14.5%, p = 0.11). The stem-cell mobilization regimen for both cohorts was predominantly cyclophosphamide and granulocyte colony-stimulating factor (gcsf). Plerixafor was used more often for the CyBorD cohort (p = 0.009), and more collection failures occurred in the CyBorD cohort (p = 0.08). In patients receiving Bor-Dex, more cells were collected (9.9×106 cells/kg vs. 7.7×106cells/kg, p = 0.007). At day +100, a very good partial response or better was achieved in 75% of the CyBorD cohort and in 73% of the Bor-Dex cohort (p = 0.77). Median pfs was 3.2 years in the Bor-Dex cohort and 3.7 years in the CyBorD cohort (p = 0.56). Conclusions: Overall efficacy was similar in our patients receiving CyBorD and Bor-Dex. After ahsct, no difference in depth of response or pfs was observed. Cyclophosphamide-gcsf seems to increase collection failures and hospitalizations in patients receiving CyBorD. Prospective studies are required to examine that relationship.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bortezomib/therapeutic use , Cyclophosphamide/therapeutic use , Dexamethasone/therapeutic use , Hematopoietic Stem Cell Transplantation/methods , Multiple Myeloma/drug therapy , Multiple Myeloma/therapy , Transplantation Conditioning/methods , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Bortezomib/pharmacology , Cyclophosphamide/pharmacology , Dexamethasone/pharmacology , Humans , Middle Aged , Retrospective StudiesABSTRACT
The UK National Diabetes Inpatient COVID Response Group was formed at the end of March 2020 to support the provision of diabetes inpatient care during the COVID pandemic. It was formed in response to two emerging needs. First to ensure that basic diabetes services are secured and maintained at a time when there was a call for re-deployment to support the need for general medical expertise across secondary care services. The second was to provide simple safe diabetes guidelines for use by specialists and non-specialists treating inpatients with or suspected of COVID-19 infection. To date the group, comprising UK-based specialists in diabetes, pharmacy and psychology, have produced two sets of guidelines which will be continually revised as new evidence emerges. It is supported by Diabetes UK, the Association of British Clinical Diabetologists and NHS England.
Subject(s)
Coronavirus Infections/therapy , Delivery of Health Care/methods , Diabetes Mellitus/therapy , Hospitalization , Pneumonia, Viral/therapy , Betacoronavirus , COVID-19 , Coronavirus Infections/epidemiology , Coronavirus Infections/metabolism , Diabetes Mellitus/epidemiology , Disease Management , Humans , Pandemics , Patient Readmission , Pneumonia, Viral/epidemiology , Pneumonia, Viral/metabolism , SARS-CoV-2 , United Kingdom/epidemiologySubject(s)
Diabetes Mellitus , Hyperglycemia , Betacoronavirus , COVID-19 , Coronavirus Infections , Humans , Inpatients , Pandemics , Pneumonia, Viral , SARS-CoV-2Subject(s)
Betacoronavirus , Diabetic Ketoacidosis , Pneumonia, Viral , COVID-19 , Coronavirus Infections , Humans , Pandemics , SARS-CoV-2ABSTRACT
INTRODUCTION: Mouse double minute 2 protein (MDM2), a negative regulator of the p53 tumour suppressor gene, is frequently amplified in malignancies. MDM2 antagonists have shown efficacy in treating malignancies with MDM2 overexpression and can overcome chemoresistance in acute myeloid leukemia. We systematically evaluated the safety profile of MDM2 inhibitors in the treatment of solid organ and hematologic malignancies. MATERIALS AND METHODS: We searched Medline and EMBASE from January 1947 to November 2018 for prospective clinical studies, in English or French, investigating any MDM2 inhibitor in pediatric or adult cancers, and reporting dose and toxicity outcomes. Primary outcome was dose-limiting toxicity (DLT) and secondary outcome was death. RESULTS: The search yielded 493 non-duplicate citations. Eighteen studies of 10 inhibitors met inclusion criteria (total N = 1005 patients). Two-thirds of included studies did not define DLTs and the reporting of toxicities was highly variable. The most commonly reported DLTs were cytopenias, gastrointestinal toxicity, metabolic disturbances, fatigue and cardiovascular toxicity; there was one death attributed to treatment toxicity. CONCLUSION: MDM2 antagonists have been studied in a variety of malignancies with toxicities similar to other commonly used chemotherapy agents and may represent a safe adjuvant treatment for further study in in acute leukemia.
Subject(s)
Antineoplastic Agents/adverse effects , Drug-Related Side Effects and Adverse Reactions/diagnosis , Hematologic Neoplasms/drug therapy , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Drug-Related Side Effects and Adverse Reactions/etiology , Evaluation Studies as Topic , Hematologic Neoplasms/pathology , Humans , Maximum Tolerated Dose , PrognosisABSTRACT
The only curative treatment option for relapsed patients with acute myeloid leukemia (AML) is allogeneic stem cell transplantation. Depletion of hematopoietic stem cells and leukemic blast cells is achieved through the systemic administration of DNA damaging agents, including total-body irradiation (TBI) prior to transplantation. Since other tissues are radiosensitive, the identification of biomarkers could facilitate the management of additional toxicities. Buccal keratinocytes are readily accessible and could provide a source of cells for RNA analysis. In this study, we obtained miRNAs and mRNAs from daily buccal swabs collected from patients undergoing allogeneic stem cell transplantation. Unexpectedly, there was no prominent p53-induced mRNA or miRNA response in these samples, despite the fact that the p53 pathway is a well-characterized radiation-inducible response. Instead, the expression of mRNAs encoding p53 and cytokeratin 14 (TP53 and KRT14, respectively) decreased precipitously within hours of the first radiation treatment. These patients went on to develop oral mucositis, however, it is unclear whether TP53 and/or KRT14 expression are predictive of this adverse event. Larger scale analysis of buccal epithelial samples from patients undergoing allogeneic stem cell transplantation appears to be warranted.
Subject(s)
Gene Expression Regulation, Neoplastic/radiation effects , Hematopoietic Stem Cell Transplantation , Keratin-14/genetics , Mouth Mucosa/radiation effects , Tumor Suppressor Protein p53/genetics , Whole-Body Irradiation/adverse effects , Female , Humans , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/radiotherapy , Leukemia, Myeloid, Acute/surgery , Male , Middle Aged , Mouth Mucosa/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Time Factors , Transplantation, HomologousABSTRACT
Burkholderia pseudomallei is a Gram-negative intracellular bacterium that causes the disease melioidosis. The disease can be fatal if left untreated or when antibiotic therapy is delayed and total clearance of the pathogen from the host is often not accomplished with current therapies. Thus, new therapeutic approaches for the treatment of infections caused by B. pseudomallei are required. To better understand host responses to B. pseudomallei infection, the activation of key proteins involved in the TLR inflammatory cascade was measured by western blotting. Activation of the mitogen-activated protein kinases (MAPKs) p38 and ERK were both significantly altered during both in vitro and in vivo infection. In considering an approach for therapy of B. pseudomallei infection the inhibition of ERK was achieved in vitro using the inhibitor PD0325901, along with decreased TNF-α production. However, the reduction in phosphorylated ERK and TNF-α release did not correspond with decreased bacterial replication or enhance clearance from infected macrophages. Despite this apparent lack of effect on the intracellular growth of B. pseudomallei in vitro, it is not clear what effect inhibition of ERK activation might have on outcome of disease in vivo. It may be that decreasing the levels of TNF-α in vivo could aid in reducing the overactive immune response that is known to ensue following B. pseudomallei infection, thereby increasing host survival.
Subject(s)
Burkholderia pseudomallei/growth & development , Chemokine CCL2/biosynthesis , Extracellular Signal-Regulated MAP Kinases/metabolism , Melioidosis/pathology , Tumor Necrosis Factor-alpha/biosynthesis , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Benzamides/pharmacology , Burkholderia pseudomallei/immunology , Burkholderia pseudomallei/metabolism , Cell Line , Diphenylamine/analogs & derivatives , Diphenylamine/pharmacology , Enzyme Activation , Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors , Female , Macrophages/microbiology , Melioidosis/immunology , Melioidosis/microbiology , Mice , Mice, Inbred BALB CABSTRACT
Francisella tularensis is a Gram-negative intracellular bacterium that causes the disease tularemia. The disease can be fatal if left untreated and there is currently no licenced vaccine available; the identification of new therapeutic targets is therefore required. Toll-like receptors represent an interesting target for therapeutic modulation due to their essential role in generating immune responses. In this study, we analysed the in vitro expression of the key mitogen-activated protein kinases (MAPKs) p38, JNK and ERK in murine alveolar macrophages during infection with F. tularensis. The phosphorylation profile of ERK highlighted its potential as a target for therapeutic modulation and subsequently the effect of ERK manipulation was measured in a lethal intranasal F. tularensis in vivo model of infection. The selective ERK1/2 inhibitor PD0325901 was administered orally to mice either pre- or post-challenge with F. tularensis strain LVS. Both treatment regimens selectively reduced ERK expression, but only the pre-exposure treatment produced decreased bacterial burden in the spleen and liver, which correlated with a significant reduction in the pro-inflammatory cytokines IFN-γ, MCP-1, IL-6, and TNF-α. However, no overall improvements in survival were observed for treated animals in this study. ERK may represent a useful therapeutic target where selective dampening of the immune response (to control the damaging pathology seen during infection) is combined with antibiotic treatment required to eradicate bacterial infection. This combination treatment strategy has been shown to be effective in other models of tularemia.
Subject(s)
Extracellular Signal-Regulated MAP Kinases/biosynthesis , Host-Pathogen Interactions , Tularemia/pathology , Animals , Bacterial Load , Benzamides/administration & dosage , Cell Line , Cytokines/metabolism , Diphenylamine/administration & dosage , Diphenylamine/analogs & derivatives , Disease Models, Animal , Female , Gene Expression Profiling , Liver/microbiology , Liver/pathology , Macrophages, Alveolar/enzymology , Macrophages, Alveolar/parasitology , Mice, Inbred BALB C , Protein Kinase Inhibitors/administration & dosage , Spleen/microbiology , Spleen/pathology , Treatment OutcomeABSTRACT
The decidua is the superficial portion of endometrium that transforms, or decidualizes, under the influence of progesterone to nourish the early embryo during pregnancy. Deciduae outside the uterus are found in nearly 100% of human pregnancies. This condition, known as deciduosis, may mimic malignancy, resulting in additional diagnostic procedures that place the mother, baby, or both at risk. Deciduosis has been described in both Old World and New World nonhuman primates in conjunction with pregnancy and after treatment with exogenous progestins. Here the authors present 6 cases of deciduosis associated with endometriotic lesions in female rhesus and cynomolgus macaques (Macaca mulatta and Macaca fascicularis). Full diagnostic necropsies with histologic analyses were performed on all animals. Deciduae were stained with hematoxylin and eosin and by immunohistochemistry for vimentin, CD10, progesterone receptor, estrogen receptor, desmin, cytokeratin, kermix P8, chorionic gonadotropin, human placental lactogen, and calretinin. The most common clinical signs were abdominal pain (4 of 6) and anorexia (2 of 6). At necropsy, macaque uteri were often enlarged or disfigured (4 of 6) with abundant fibrous adhesions (5 of 6). Affected tissue consisted of epithelial-lined cysts and decidualized stroma with scattered gamma/delta T cells. Decidualized stromal cells were large and polyhedral with abundant cytoplasm and round vesicular nuclei. They stained positive for vimentin, CD10, progesterone, and estrogen. In summary, these cases illustrate deciduosis in 6 nonhuman primates with endometriosis. Understanding decidualization in nonhuman primates will aid in elucidating the pathophysiology of deciduosis during pregnancy or endometriosis and potentially lead to new interventions.
Subject(s)
Decidua/pathology , Endometriosis/veterinary , Monkey Diseases/pathology , Animals , Endometriosis/pathology , Endometrium/pathology , Female , Macaca fascicularis , Macaca mulattaABSTRACT
Due to cancer's genetic complexity, significant advances in the treatment of metastatic disease will require sophisticated, multi-pronged therapeutic approaches. Here we demonstrate the utility of a Drosophila melanogaster cell platform for the production and in vivo delivery of multi-gene biotherapeutic systems. We show that cultured Drosophila S2 cell carriers can stably propagate oncolytic viral therapeutics that are highly cytotoxic for mammalian cancer cells without adverse effects on insect cell viability or gene expression. Drosophila cell carriers administered systemically to immunocompetent animals trafficked to tumors to deliver multiple biotherapeutics with little apparent off-target tissue homing or toxicity, resulting in a therapeutic effect. Cells of this Dipteran invertebrate provide a genetically tractable platform supporting the integration of complex, multi-gene biotherapies while avoiding many of the barriers to systemic administration of mammalian cell carriers. These transporters have immense therapeutic potential as they can be modified to express large banks of biotherapeutics with complementary activities that enhance anti-tumor activity.
Subject(s)
Drosophila melanogaster/genetics , Genetic Therapy/methods , Lung Neoplasms/therapy , Oncolytic Virotherapy/methods , Oncolytic Viruses/genetics , Animals , Chlorocebus aethiops , Drosophila melanogaster/cytology , Drosophila melanogaster/immunology , Drosophila melanogaster/virology , Female , Gene Expression Regulation, Neoplastic , Gene Expression Regulation, Viral , HT29 Cells , HeLa Cells , Humans , Immunocompetence , Lung Neoplasms/genetics , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Lung Neoplasms/virology , MCF-7 Cells , Mice, Inbred BALB C , Oncolytic Viruses/immunology , Oncolytic Viruses/pathogenicity , Time Factors , Transfection , Tumor Burden , Vero Cells , Xenograft Model Antitumor AssaysABSTRACT
AIMS: The Ipswich Touch Test is a novel method to detect subjects with diabetes with loss of foot sensation and is simple, safe, quick, and easy to perform and teach. This study determines whether it can be used by relatives and/or carers to detect reduced foot sensation in the setting of the patient's home. METHODS: The test involves lightly and briefly (1-2 s) touching the tips of the first, third and fifth toes of both feet with the index finger. Reduced foot sensation was defined as ≥ 2 insensate areas. Patients due to attend clinic over a 4-week period were invited by post. The invitation contained detailed instructions and a sheet for recording the results. The findings were compared with those obtained in clinic using the 10-g monofilament at the same six sites. RESULTS: Of 331 patients (174 males), 25.1% (n = 83) had ≥ 2 insensate areas to 10-g monofilament testing. Compared with this, the Ipswich Touch Test at home had a sensitivity of 78.3% and a specificity of 93.9%. The predictive values of detecting 'at-risk' feet were positive at 81.2% and negative at 92.8%. The likelihood ratios were positive at 12.9 and negative at 0.23. CONCLUSIONS: With clearly written instructions, this simple test can be used by non-professionals to accurately assess for loss of protective sensation. We believe that the Ipswich Touch Test may also be a useful educational adjunct to improve awareness of diabetes foot disease in patients and relatives alike and empower them to seek appropriate care if sensation was found to be abnormal.
Subject(s)
Diabetic Foot/diagnosis , Diabetic Neuropathies/diagnosis , Self Care , Delivery of Health Care , Diabetic Foot/physiopathology , Diabetic Foot/prevention & control , Diabetic Neuropathies/physiopathology , Female , Humans , Male , Middle Aged , Patient Education as Topic , Power, Psychological , Predictive Value of Tests , Reproducibility of Results , Risk Assessment , Sensitivity and Specificity , Sensory Thresholds , Treatment OutcomeABSTRACT
BACKGROUND: Individuals with MS undergoing immunoablative therapy and hematopoietic stem cell transplantation (HSCT) show substantial decrease in brain volume over 2.4 months, presumably from chemotoxic effects, although other mechanisms have also been postulated. OBJECTIVE: We examined whether volume loss was accompanied by a concomitant decrease in cognition. White and gray matter volumes, and the effect of stem cell dosage were considered. METHODS: Seven individuals with rapidly progressing MS and poor prognosis underwent high dose immunosuppression and autologous HSCT. Neuropsychological testing and MRI scans were performed at baseline, 2 and 24 months post-procedure. RESULTS: Cognitive impairment was noted at all times in most participants. Median decline of 1.39% in total brain volume was noted 2 months post-HSCT. By 24 months a further decline of 1.65% was noted. At 2 months significant decline was observed for areas of executive functioning. At 24 months almost no significant declines were noted. No significant correlations were found between cognitive decline and change in imaging variables or stem cell dosage. CONCLUSIONS: Cognition changed in the early period following treatment but with little apparent relationship to volume changes. With temporal distance from the HSCT procedure, cognition returned to baseline levels. With the caution of a very small sample, preliminary results suggest that immunoablation and HSCT may have no lasting deleterious effects on cognition.
ABSTRACT
Rhabdoviruses (RVs) are currently being pursued as anticancer therapeutics for various tumor types, notably leukemia. However, modest virion production and limited spread between noncontiguous circulating leukemic cells requires high-dose administration of RVs, which exceeds the maximum tolerable dose of the live virus. Furthermore, in severely immunosuppressed leukemic patients, the potential for uncontrolled live virus spread may compromise the safety of a live virus approach. We hypothesized that the barriers to oncolytic virotherapy in liquid tumors may be overcome by administration of high-dose non-replicating RVs. We have developed a method to produce unique high-titer bioactive yet non-replicating rhabdovirus-derived particles (NRRPs). This novel biopharmaceutical is multimodal possessing direct cytolytic and immunomodulatory activity against acute leukemia. We demonstrate that NRRP resistance in normal cells is mediated by intact antiviral defences including interferon (IFN). This data was substantiated using murine models of blast crisis. The translational promise of NRRPs was demonstrated in clinical samples obtained from patients with high-burden multidrug-resistant acute myeloid leukemia. This is the first successful attempt to eradicate disseminated cancer using a non-replicating virus-derived agent, representing a paradigm shift in our understanding of oncolytic virus-based therapies and their application toward the treatment of acute leukemia.
ABSTRACT
It may seem obvious that continuous renal replacement therapy (CRRT) means that the treatment is truly continuous--administered without interruption on a 24/7 basis. In reality, a number of barriers limit the continuous aspect of CRRT. This article describes how nursing staff of an inpatient dialysis unit in a large Midwestern academic institution identified these barriers and developed and implemented a multifaceted plan to optimize CRRT.
Subject(s)
Kidney Failure, Chronic/therapy , Renal Replacement Therapy , Education, Nursing, Continuing , HumansABSTRACT
BACKGROUND: Haematopoietic stem cell transplantation (HSCT) has been tried in the last 15 years as a therapeutic option in patients with poor-prognosis autoimmune disease who do not respond to conventional treatments. Worldwide, more than 600 patients with multiple sclerosis (MS) have been treated with HSCT, most of them having been recruited in small, single-centre, phase 1-2 uncontrolled trials. Clinical and magnetic resonance imaging outcomes from case series reports or Registry-based analyses suggest that a major response is achieved in most patients; quality and duration of response are better in patients transplanted during the relapsing-remitting phase than in those in the secondary progressive stage. OBJECTIVES: An interdisciplinary group of neurologists and haematologists has been formed, following two international meetings supported by the European and American Blood and Marrow Transplantation Societies, for the purpose of discussing a controlled clinical trial, to be designed within the new scenarios of evolving MS treatments. CONCLUSIONS: Objectives of the trial, patient selection, transplant technology and outcome assessment were extensively discussed. The outcome of this process is summarized in the present paper, with the goal of establishing the background and advancing the development of a prospective, randomized, controlled multicentre trial to assess the clinical efficacy of HSCT for the treatment of highly active MS.
Subject(s)
Clinical Trials, Phase III as Topic/methods , Hematopoietic Stem Cell Transplantation , Multicenter Studies as Topic/methods , Multiple Sclerosis, Relapsing-Remitting/surgery , Randomized Controlled Trials as Topic/methods , Research Design , Adolescent , Adult , Cooperative Behavior , Disability Evaluation , Europe , Humans , International Cooperation , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Prospective Studies , Severity of Illness Index , Transplantation, Autologous , Treatment Outcome , United States , Young AdultSubject(s)
Gastrointestinal Diseases , Hematopoietic Stem Cell Transplantation/adverse effects , Kidney Diseases , Liver Diseases , Stomatitis , Adult , Female , Gastrointestinal Diseases/etiology , Gastrointestinal Diseases/therapy , Graft vs Host Disease/prevention & control , Hematologic Neoplasms/therapy , Humans , Kidney Diseases/etiology , Kidney Diseases/therapy , Kinetics , Liver Diseases/etiology , Liver Diseases/therapy , Male , Middle Aged , Stomatitis/etiology , Stomatitis/therapy , Transplantation, Autologous , Transplantation, HomologousABSTRACT
Identification of genes that regulate clonogenicity of acute myelogenous leukemia (AML) cells is hindered by the difficulty of isolating pure populations of cells with defined proliferative abilities. By analyzing the growth of clonal siblings in low passage cultures of the cell line OCI/AML4 we resolved this heterogeneous population into strata of distinct clonogenic potential, permitting analysis of the transcriptional signature of single cells with defined proliferative abilities. By microarray analysis we showed that the expression of the orphan nuclear receptor EAR-2 (NR2F6) is greater in leukemia cells with extensive proliferative capacity than in those that have lost proliferative ability. EAR-2 is expressed highly in long-term hematopoietic stem cells, relative to short-term hematopoietic stem and progenitor cells, and is downregulated in AML cells after induction of differentiation. Exogenous expression of EAR-2 increased the growth of U937 cells and prevented the proliferative arrest associated with terminal differentiation, and blocked differentiation of U937 and 32Dcl3 cells. Conversely, silencing of EAR-2 by short-hairpin RNA initiated terminal differentiation of these cell lines. These data identify EAR-2 as an important factor in the regulation of clonogenicity and differentiation, and establish that analysis of clonal siblings allows the elucidation of differences in gene expression within the AML hierarchy.