X chromosome aneuploidies have long been associated with human cancers, but causality has not been established. In mammals, X chromosome inactivation (XCI) is triggered by Xist RNA to equalize gene ...expression between the sexes. Here we delete Xist in the blood compartment of mice and demonstrate that mutant females develop a highly aggressive myeloproliferative neoplasm and myelodysplastic syndrome (mixed MPN/MDS) with 100% penetrance. Significant disease components include primary myelofibrosis, leukemia, histiocytic sarcoma, and vasculitis. Xist-deficient hematopoietic stem cells (HSCs) show aberrant maturation and age-dependent loss. Reconstitution experiments indicate that MPN/MDS and myelofibrosis are of hematopoietic rather than stromal origin. We propose that Xist loss results in X reactivation and consequent genome-wide changes that lead to cancer, thereby causally linking the X chromosome to cancer in mice. Thus, Xist RNA not only is required to maintain XCI but also suppresses cancer in vivo.
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► Deleting Xist causes blood cancer ► Overdosage of the X chromosome causes cancer ► Xist is required for hematopoietic stem cell survival and function ► Deleting Xist causes marrow fibrosis, leukemia, and histiocytic sarcoma
Deletion of Xist in the blood cells of female mice causes an aggressive and highly penetrant hematopoietic cancer.
Progenitor cells that are the basis for all blood cell production share the bone marrow with more mature elements of the adaptive immune system. Specialized niches within the bone marrow guide and, ...at times, constrain the development of haematopoietic stem and progenitor cells (HSPCs) and lineage-restricted immune progenitor cells. Specific niche components are organized into distinct domains to create a diversified landscape in which specialized cell differentiation or population expansion programmes proceed. Local cues that reflect the tissue and organismal state affect cellular interactions to alter the production of a range of cell types. Here, we review the organization of regulatory elements in the bone marrow and discuss how these elements provide a dynamic means for the host to modulate stem cell and adaptive immune cell responses to physiological challenges.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Differentiation therapy has proven to be a success story for patients with acute promyelocytic leukemia. However, the remaining subtypes of acute myeloid leukemia (AML) are treated with cytotoxic ...chemotherapies that have limited efficacy and a high likelihood of resistance. As differentiation arrest is a hallmark of AML, there is increased interest in developing differentiation-inducing agents to enhance disease-free survival. Here, we provide a comprehensive review of current reports and future avenues of nucleic acid therapeutics for AML, focusing on the use of targeted nucleic acid drugs to promote differentiation. Specifically, we compare and discuss the precision of small interfering RNA, small activating RNA, antisense oligonucleotides, and aptamers to modulate gene expression patterns that drive leukemic cell differentiation. We delve into preclinical and clinical studies that demonstrate the efficacy of nucleic acid-based differentiation therapies to induce leukemic cell maturation and reduce disease burden. By directly influencing the expression of key genes involved in myeloid maturation, nucleic acid therapeutics hold the potential to induce the differentiation of leukemic cells towards a more mature and less aggressive phenotype. Furthermore, we discuss the most critical challenges associated with developing nucleic acid therapeutics for myeloid malignancies. By introducing the progress in the field and identifying future opportunities, we aim to highlight the power of nucleic acid therapeutics in reshaping the landscape of myeloid leukemia treatment.
Metallic lithium deposition on graphite anodes is a critical degradation mode in lithium-ion batteries, which limits safety and fast charge capability. A conclusive strategy to mitigate lithium ...deposition under fast charging yet remains elusive. In this work, we examine the role of electrode microstructure in mitigating lithium plating behavior under various operating conditions, including fast charging. The multilength scale characteristics of the electrode microstructure lead to a complex interaction of transport and kinetic limitations that significantly governs the cell performance and the occurrence of Li plating. We demonstrate, based on a comprehensive mesoscale analysis, that the performance and degradation can be significantly modulated via systematic design improvements at the hierarchy of length scales. It is found that the improvement in kinetic and transport characteristics achievable at disparate scales can dramatically affect Li plating propensity.
The breakfast meal often results in the largest postprandial hyperglycemic excursion in people with type 2 diabetes.
Our purpose was to investigate whether restricting carbohydrates at breakfast ...would be a simple and feasible strategy to reduce daily exposure to postprandial hyperglycemia.
Adults with physician-diagnosed type 2 diabetes n = 23; mean ± SD age: 59 ± 11 y; glycated hemoglobin: 6.7% ± 0.6%; body mass index (kg/m2): 31 ± 7 completed two 24-h isocaloric intervention periods in a random order. Participants consumed one of the following breakfasts: 1) a very-low-carbohydrate high-fat breakfast (LCBF; <10% of energy from carbohydrate, 85% of energy from fat, 15% of energy from protein) or 2) a breakfast with dietary guidelines–recommended nutrient profile (GLBF; 55% of energy from carbohydrate, 30% of energy from fat, 15% of energy from protein), with the same lunch and dinner provided. Continuous glucose monitoring was used to assess postprandial glucose responses over 24 h, and visual analog scales were used to assess ratings of hunger and fullness.
The LCBF significantly reduced postprandial hyperglycemia after breakfast (P < 0.01) and did not adversely affect glycemia after lunch or dinner. As such, overall postprandial hyperglycemia (24-h incremental area under the glucose curve) and glycemic variability (mean amplitude of glycemic excursions) were reduced with the LCBF (24-h incremental area under the glucose curve: −173 ± 361 mmol/L; P = 0.03; mean amplitude of glycemic excursions: −0.4 ± 0.8 mmol/L · 24 h; P = 0.03) compared with the GLBF. Premeal hunger was lower before dinner with the LCBF than with the GLBF (P-interaction = 0.03).
A very-low-carbohydrate high-fat breakfast lowers postbreakfast glucose excursions. The effects of this simple strategy appear to be sufficient to lower overall exposure to postprandial hyperglycemia and improve glycemic variability. Longer-term interventions are warranted. This trial was registered at clinicaltrials.gov as NCT02982330.
Hematopoietic stem cell transplantation is a potential curative therapy for malignant and nonmalignant diseases. Improving the efficiency of stem cell collection and the quality of the cells acquired ...can broaden the donor pool and improve patient outcomes. We developed a rapid stem cell mobilization regimen utilizing a unique CXCR2 agonist, GROβ, and the CXCR4 antagonist AMD3100. A single injection of both agents resulted in stem cell mobilization peaking within 15 min that was equivalent in magnitude to a standard multi-day regimen of granulocyte colony-stimulating factor (G-CSF). Mechanistic studies determined that rapid mobilization results from synergistic signaling on neutrophils, resulting in enhanced MMP-9 release, and unexpectedly revealed genetic polymorphisms in MMP-9 that alter activity. This mobilization regimen results in preferential trafficking of stem cells that demonstrate a higher engraftment efficiency than those mobilized by G-CSF. Our studies suggest a potential new strategy for the rapid collection of an improved hematopoietic graft.
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•GROβ is well tolerated and induces mobilization in a first in-human study•Combination treatment with GROβ+AMD3100 results in rapid stem cell mobilization•Mouse strain nucleotide polymorphisms in MMP-9 alter biologic activity•Rapid mobilization releases a highly engraftable hematopoietic stem cell
A new strategy for stem cell mobilization enables rapid collection of an improved hematopoietic graft in humans.
Sorafenib is an oral anticancer agent targeting Ras-dependent signaling and angiogenic pathways. A phase I trial demonstrated that the combination of gemcitabine and sorafenib was well tolerated and ...had activity in advanced pancreatic cancer (APC) patients. The BAYPAN study was a multicentric, placebo-controlled, double-blind, randomized phase III trial comparing gemcitabine/sorafenib and gemcitabine/placebo in the treatment of APC.
The patient eligibility criteria were locally advanced or metastatic pancreatic adenocarcinoma, no prior therapy for advanced disease and a performance status of zero to two. The primary end point was progression-free survival (PFS). The patients received gemcitabine 1000 mg/m2 i.v., weekly seven times followed by 1 rest week, then weekly three times every 4 weeks plus sorafenib 200 mg or placebo, two tablets p.o., twice daily continuously.
Between December 2006 and September 2009, 104 patients were enrolled on the study (52 pts in each arm) and 102 patients were treated. The median and the 6-month PFS were 5.7 months and 48% for gemcitabine/placebo and 3.8 months and 33% for gemcitabine/sorafenib (P = 0.902, stratified log-rank test), respectively. The median overall survivals were 9.2 and 8 months, respectively (P = 0.231, log-rank test). The overall response rates were similar (19 and 23%, respectively).
The addition of sorafenib to gemcitabine does not improve PFS in APC patients.
Bioengineered lungs produced from patient-derived cells may one day provide an alternative to donor lungs for transplantation therapy. Here we report the regeneration of functional pulmonary ...vasculature by repopulating the vascular compartment of decellularized rat and human lung scaffolds with human cells, including endothelial and perivascular cells derived from induced pluripotent stem cells. We describe improved methods for delivering cells into the lung scaffold and for maturing newly formed endothelium through co-seeding of endothelial and perivascular cells and a two-phase culture protocol. Using these methods we achieved ∼75% endothelial coverage in the rat lung scaffold relative to that of native lung. The regenerated endothelium showed reduced vascular resistance and improved barrier function over the course of in vitro culture and remained patent for 3 days after orthotopic transplantation in rats. Finally, we scaled our approach to the human lung lobe and achieved efficient cell delivery, maintenance of cell viability and establishment of perfusable vascular lumens.
The WHO urges action against the threat posed by HIV drug resistance. It is well known that the sensitivity of Next-Generation Sequencing (NGS) is greater than that of Sanger Sequencing (SS). The ...objective of this study was to evaluate the performance of the novel NGS HIV-1 drug resistance monitoring system.
NGS analyses were performed on 67 plasma samples from HIV-1 infected patients using the Sentosa SQ HIV Genotyping Assay from Vela-Dx. This kit was used on a semi-automated Ion Torrent-based platform. Sequences were compared to those obtained by SS. Samples were analysed in the same and in separate runs. Quality controls (QC) were added to control sequencing processes of protease (PRO), reverse transcriptase (RT) and integrase (INT) regions.
Of the 41 analysed samples, 33 (80.5%) had identical drug resistance interpretation reports. Discrepant results were observed for eight samples. Five of them were only detected by NGS and had drug resistance mutations (DRMs) with an allelic frequency below the limit of detection of the SS method (between 6.3 to 20.5%). Two DRMs were only identified using the SS method. The sequences were similar in 98.2% of cases (counting variants as mismatches) and homologous in 99.9% if missed variants. Duplicated samples in a single run were similar in 95.7% (99.9%) of cases. Duplicated samples in two different runs were 98% (100%) homologous. QC results were manually assessed with a score of 340/340 for detection of DRMs in PRO and RT and 100% for INT sequencing.
This is the first preliminary evaluation in Belgium employing the Sentosa SQ HIV Genotyping Assay. The NGS appears to be a promising tool for the detection of DRMs in HIV-1 patients and showed a higher sensitivity compared to SS. Large studies assessing the clinical relevance of low frequency DRMs are needed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Summary Background Hypomethylating drugs are the standard treatment for patients with high-risk myelodysplastic syndromes. Survival is poor after failure of these drugs; there is no approved ...second-line therapy. We compared the overall survival of patients receiving rigosertib and best supportive care with that of patients receiving best supportive care only in patients with myelodysplastic syndromes with excess blasts after failure of azacitidine or decitabine treatment. Methods We did this randomised controlled trial at 74 hospitals and university medical centres in the USA and Europe. We enrolled patients with diagnosis of refractory anaemia with excess blasts (RAEB)-1, RAEB-2, RAEB-t, or chronic myelomonocytic leukaemia based on local site assessment, and treatment failure with a hypomethylating drug in the past 2 years. Patients were randomly assigned (2:1) to receive rigosertib 1800 mg per 24 h via 72-h continuous intravenous infusion administered every other week or best supportive care with or without low-dose cytarabine. Randomisation was stratified by pretreatment bone marrow blast percentage. Neither patients nor investigators were masked to treatment assignment. The primary outcome was overall survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov , NCT01241500. Findings From Dec 13, 2010, to Aug 15, 2013, we enrolled 299 patients: 199 assigned to rigosertib, 100 assigned to best supportive care. Median follow-up was 19·5 months (IQR 11·9–27·3). As of Feb 1, 2014, median overall survival was 8·2 months (95% CI 6·1–10·1) in the rigosertib group and 5·9 months (4·1–9·3) in the best supportive care group (hazard ratio 0·87, 95% CI 0·67–1·14; p=0·33). The most common grade 3 or higher adverse events were anaemia (34 18% of 184 patients in the rigosertib group vs seven 8% of 91 patients in the best supportive care group), thrombocytopenia (35 19% vs six 7%), neutropenia (31 17% vs seven 8%), febrile neutropenia (22 12% vs ten 11%), and pneumonia (22 12% vs ten 11%). 41 (22%) of 184 patients in the rigosertib group and 30 (33%) of 91 patients in the best supportive care group died due to adverse events and three deaths were attributed to rigosertib treatment. Interpretation Rigosertib did not significantly improve overall survival compared with best supportive care. A randomised phase 3 trial of rigosertib ( NCT 02562443 ) is underway in specific subgroups of patients deemed to be at high risk, including patients with very high risk per the Revised International Prognostic Scoring System criteria. Funding Onconova Therapeutics, Leukemia & Lymphoma Society.
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