The non-coding RNA landscape of human hematopoiesis and leukemia

© The Author(s) 2017. Non-coding RNAs have emerged as crucial regulators of gene expression and cell fate decisions. However, their expression patterns and regulatory functions during normal and malignant human hematopoiesis are incompletely understood. Here we present a comprehensive resource defining the non-coding RNA landscape of the human hematopoietic system. Based on highly specific non-coding RNA expression portraits per blood cell population, we identify unique fingerprint non-coding RNAs-such as LINC00173 in granulocytes-and assign these to critical regulatory circuits involved in blood homeostasis. Following the incorporation of acute myeloid leukemia samples into the landscape, we further uncover prognostically relevant non-coding RNA stem cell signatures shared between acute myeloid leukemia blasts and healthy hematopoietic stem cells. Our findings highlight the importance of the non-coding transcriptome in the formation and maintenance of the human blood hierarchy

Creation of multiple nanodots by single ions

In the challenging search for tools that are able to modify surfaces on the nanometer scale, heavy ions with energies of several 10 MeV are becoming more and more attractive. In contrast to slow ions where nuclear stopping is important and the energy is dissipated into a large volume in the crystal, in the high energy regime the stopping is due to electronic excitations only. Because of the extremely local (< 1 nm) energy deposition with densities of up to 10E19 W/cm^2, nanoscaled hillocks can be created under normal incidence. Usually, each nanodot is due to the impact of a single ion and the dots are randomly distributed. We demonstrate that multiple periodically spaced dots separated by a few 10 nanometers can be created by a single ion if the sample is irradiated under grazing angles of incidence. By varying this angle the number of dots can be controlled.Comment: 12 pages, 6 figure

Therapy reduction in patients with Down syndrome and myeloid leukemia: the international ML-DS 2006 trial

Children with myeloid leukemia associated with Down syndrome (ML-DS) have superior outcome compared with non-DS patients, but suffer from higher constitutional cytotoxic drug susceptibility. We analyzed the outcome of 170 pediatric patients with ML-DS enrolled in the prospective, multicenter, open-label, nonrandomized ML-DS 2006 trial by Nordic Society for Pediatric Hematology and Oncology (NOPHO), Dutch Childhood Oncology Group (DCOG), and Acute Myeloid Leukemia–Berlin-Frankfurt-Münster (AML-BFM) study group. Compared with the historical control arm (reduced-intensity protocol for ML-DS patients from the AML-BFM 98 trial), treatment intensity was reduced by lowering the cumulative dose of etoposide (950 to 450 mg/m2) and intrathecal central nervous system prophylaxis while omitting maintenance therapy. Still, 5-year overall survival (89% 6 3% vs 90% 6 4%; Plog-rank 5 .64), event-free survival (EFS; 87% 6 3% vs 89% 6 4%; Plog-rank 5 .71), and cumulative incidence of relapse/ nonresponse (CIR/NR; 6% 6 3% vs 6% 6 2%; PGray 5 .03) did not significantly differ between the ML-DS 2006 trial and the historical control arm. Poor early treatment response (5-year EFS, 58% 6 16% vs 88% 6 3%; Plog rank 5 .0008) and gain of chromosome 8 (CIR/NR, 16% 6 7% vs 3% 6 2%, PGray 5 .02; 5-year EFS, 73% 6 8% vs 91% 6 4%, Plog rank 5 .018) were identified as independent prognostic factors predicting a worse EFS. Five of 7 relapsed patients (71%) with cytogenetic data had trisomy 8. Our study reveals prognostic markers for children with ML-DS and illustrates that reducing therapy did not impair excellent outcome. The trial was registered at EudraCT as #2007-006219-2. (Blood. 2017;129(25): 3314-3321

MicroRNA-106b~25 cluster is upregulated in relapsed MLL-rearranged pediatric acute myeloid leukemia

The most important reason for therapy failure in pediatric acute myeloid leukemia (AML) is relapse. In order to identify miRNAs that contribute to the clonal evolution towards relapse in pediatric AML, miRNA expression profiling of 127 de novo pediatric AML cases were used. In the diagnostic phase, no miRNA signatures could be identified that were predictive for relapse occurrence, in a large pediatric cohort, nor in a nested mixed lineage leukemia (MLL)-rearranged pediatric cohort. AML with MLL- rearrangements are found in 15-20% of all pediatric AML samples, and reveal a relapse rate up to 50% for certain translocation partner subgroups. Therefore, microRNA expression profiling of six paired initial diagnosis-relapse MLL-rearranged pediatric AML samples (test cohort) and additional eight paired initial diagnosisrelapse samples with MLL-rearrangements (validation cohort) was performed. A list of 53 differentially expressed miRNAs was identified of which the miR-106b~25 cluster, located in intron 13 of MCM7, was the most prominent. These differentially expressed miRNAs however could not predict a relapse in de novo AML samples with MLLrearrangements at diagnosis. Furthermore, higher mRNA expression of both MCM7 and its upstream regulator E2F1 was found in relapse samples with MLL-rearrangements. In conclusion, we identified the miR-106b~25 cluster to be upregulated in relapse pediatric AML with MLL-rearrangements

Rationale and design for SHAREHD: a quality improvement collaborative to scale up Shared Haemodialysis Care for patients on centre based haemodialysis.

BACKGROUND: The study objective is to assess the effectiveness and economic impact of a structured programme to support patient involvement in centre-based haemodialysis and to understand what works for whom in what circumstances and why. It implements a program of Shared Haemodialysis Care (SHC) that aims to improve experience and outcomes for those who are treated with centre-based haemodialysis, and give more patients the confidence to dialyse independently both at centres and at home. METHODS/DESIGN: The 24 month mixed methods cohort evaluation of 600 prevalent centre based HD patients is nested within a 30 month quality improvement program that aims to scale up SHC at 12 dialysis centres across England. SHC describes an intervention where patients who receive centre-based haemodialysis are given the opportunity to learn, engage with and undertake tasks associated with their treatment. Following a 6-month set up period, a phased implementation programme is initiated across 12 dialysis units using a randomised stepped wedge design with 6 centres participating in each of 2 steps, each lasting 6 months. The intervention utilises quality improvement methodologies involving rapid tests of change to determine the most appropriate mechanisms for implementation in the context of a learning collaborative. Running parallel with the stepped wedge intervention is a mixed methods cohort evaluation that employs patient questionnaires and interviews, and will link with routinely collected data at the end of the study period. The primary outcome measure is the number of patients performing at least 5 dialysis-related tasks collected using 3 monthly questionnaires. Secondary outcomes measures include: the number of people choosing to perform home haemodialysis or dialyse independently in-centre by the end of the study period; end-user recommendation; home dialysis establishment delay; staff impact and confidence; hospitalisation; infection and health economics. DISCUSSION: The results from this study will provide evidence of impact of SHC, barriers to patient and centre level adoption and inform development of future interventions to support its implementation. TRIAL REGISTRATION: ISRCTN Number: 93999549 , (retrospectively registered 1st May 2017); NIHR Research Portfolio: 31566

Whole-body MRI for staging and interim response monitoring in paediatric and adolescent Hodgkin's lymphoma: a comparison with multi-modality reference standard including 18F-FDG-PET-CT

Objectives: To prospectively investigate concordance between whole-body MRI (WB-MRI) and a composite reference standard for initial staging and interim response evaluation in paediatric and adolescent Hodgkin’s lymphoma. // Methods: Fifty patients (32 male, age range 6–19 years) underwent WB-MRI and standard investigations, including 18F-FDG-PET-CT at diagnosis and following 2–3 chemotherapy cycles. Two radiologists in consensus interpreted WB-MRI using prespecified definitions of disease positivity. A third radiologist reviewed a subset of staging WB-MRIs (n = 38) separately to test for interobserver agreement. A multidisciplinary team derived a primary reference standard using all available imaging/clinical investigations. Subsequently, a second multidisciplinary panel rereviewed all imaging with long-term follow-up data to derive an enhanced reference standard. Interobserver agreement for WB-MRI reads was tested using kappa statistics. Concordance for correct classification of all disease sites, true positive rate (TPR), false positive rate (FPR) and kappa for staging/response agreement were calculated for WB-MRI. // Results: There was discordance for full stage in 74% (95% CI 61.9–83.9%) and 44% (32.0–56.6%) of patients against the primary and enhanced reference standards, respectively. Against the enhanced reference standard, the WB-MRI TPR, FPR and kappa were 91%, 1% and 0.93 (0.90–0.96) for nodal disease and 79%, < 1% and 0.86 (0.77–0.95) for extra-nodal disease. WB-MRI response classification was correct in 25/38 evaluable patients (66%), underestimating response in 26% (kappa 0.30, 95% CI 0.04–0.57). There was a good agreement for nodal (kappa 0.78, 95% CI 0.73–0.84) and extra-nodal staging (kappa 0.60, 95% CI 0.41–0.78) between WB-MRI reads. // Conclusions: WB-MRI has reasonable accuracy for nodal and extra-nodal staging but is discordant with standard imaging in a substantial minority of patients, and tends to underestimate disease response

Endogenous tumor suppressor microRNA-193b: Therapeutic and prognostic value in acute myeloid leukemia

Purpose Dysregulated microRNAs are implicated in the pathogenesis and aggressiveness of acute myeloid leukemia (AML). We describe the effect of the hematopoietic stem-cell self-renewal regulating miR-193b on progression and prognosis of AML. Methods We profiled miR-193b-5p/3p expression in cytogenetically and clinically characterized de novo pediatric AML (n = 161) via quantitative real-time polymerase chain reaction and validated our findings in an independent cohort of 187 adult patients. We investigated the tumor suppressive function of miR-193b in human AML blasts, patient-derived xenografts, and miR-193b knockout mice in vitro and in vivo. Results miR-193b exerted important, endogenous, tumor-suppressive functions on the hematopoietic system. miR-193b-3p was downregulated in several cytogenetically defined subgroups of pediatric and adult AML, and low expression served as an independent indicator for poor prognosis in pediatric AML (risk ratio 6 standard error, 20.56 6 0.23; P = .016). miR-193b-3p expression improved the prognostic value of the European LeukemiaNet risk-group stratification or a 17-gene leukemic stemness score. In knockout mice, loss of miR-193b cooperated with Hoxa9/Meis1 during leukemogenesis, whereas restoring miR-193b expression impaired leukemic engraftment. Similarly, expression of miR-193b in AML blasts from patients diminished leukemic growth in vitro and in mouse xenografts. Mechanistically, miR-193b induced apoptosis and a G1/S-phase block in various human AML subgroups by targeting multiple factors of the KIT-RAS-RAF-MEK-ERK (MAPK) signaling cascade and the downstream cell cycle regulator CCND1. Conclusion The tumor-suppressive function is independent of patient age or genetics; therefore, restoring miR-193b would assure high antileukemic efficacy by blocking the entire MAPK signaling cascade while preventing the emergence of resistance mechanisms