Publications by authors named "Papapetrou E"

One hallmark of cancer is the upregulation and dependency on glucose metabolism to fuel macromolecule biosynthesis and rapid proliferation. Despite significant pre-clinical effort to exploit this pathway, additional mechanistic insights are necessary to prioritize the diversity of metabolic adaptations upon acute loss of glucose metabolism. Here, we investigated a potent small molecule inhibitor to Class I glucose transporters, KL-11743, using glycolytic leukemia cell lines and patient-based model systems.

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Transformative technologies to sequence tumor genomes at large scale and single-cell resolution have exposed the repertoire of genetic alterations that are present in leukemia genomes, the timing of their acquisition and patterns of their co-occurrence. In parallel, single-cell multi-omics technologies are allowing us to map the differentiation paths and hierarchical structures of malignant cells and giving us a glimpse into hematopoietic development in prenatal life. We propose that interrogating how the genetic evolution, differentiation hierarchy and ontogeny of malignant myeloid cells intersect with each other, using new experimental systems and multimodal technologies, will fuel the next generation of research breakthroughs.

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Article Synopsis
  • * The study reveals that RAS mutations transform specific blood cell progenitors (granulocyte-monocyte progenitors) that have already acquired other mutations, suggesting advanced leukemia can arise from different cell types than initial clones.
  • * RAS-mutant leukemia stem cells show resistance to the treatment drug venetoclax due to changes in gene expression, leading to worse treatment responses and relapses characterized by monocytic features, highlighting the impact of genetic drivers on therapy effectiveness.
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Telomere biology disorders (TBDs), caused by pathogenic germ line variants in telomere-related genes, present with multiorgan disease and a predisposition to cancer. Clonal hematopoiesis (CH) as a marker of cancer development and survival in TBDs is poorly understood. Here, we characterized the clonal landscape of a large cohort of 207 patients with TBD with a broad range of age and phenotype.

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Clonal hematopoiesis (CH) is a common premalignant state in the blood and confers an increased risk of blood cancers and all-cause mortality. Identification of therapeutic targets in CH has been hindered by the lack of an ex vivo platform amenable for studying primary hematopoietic stem and progenitor cells (HSPCs). Here, we utilize an ex vivo co-culture system of HSPCs with bone marrow endothelial cells to perform CRISPR/Cas9 screens in mutant HSPCs.

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Spliceosome machinery mutations are common early mutations in myeloid malignancies; however, effective targeted therapies against them are still lacking. In the current study, we used an high-throughput drug screen among four different isogenic cell lines and identified RKI-1447, a Rho-associated protein kinase inhibitor, as selective cytotoxic effector of mutant cells. RKI-1447 targeted mutated primary human samples in xenografts models.

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Increased eosinophil counts are associated with cardiovascular disease and may be an independent predictor of major cardiovascular events. However, the causality and underlying mechanisms are poorly understood. Genome-wide association studies have shown an association of a common LNK variant (R262W, T allele) with eosinophilia and atherothrombotic disorders.

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Unlabelled: RNA splicing factor (SF) gene mutations are commonly observed in patients with myeloid malignancies. Here we showed that SRSF2- and U2AF1-mutant leukemias are preferentially sensitive to PARP inhibitors (PARPi), despite being proficient in homologous recombination repair. Instead, SF-mutant leukemias exhibited R-loop accumulation that elicited an R-loop-associated PARP1 response, rendering cells dependent on PARP1 activity for survival.

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Background: Clonal hematopoiesis (CH) has emerged as an independent risk factor for atherosclerotic cardiovascular disease, with activation of macrophage inflammasomes as a potential underlying mechanism. The NLRP3 (NLR family pyrin domain containing 3) inflammasome has a key role in promoting atherosclerosis in mouse models of CH, whereas inhibition of the inflammasome product interleukin-1β appeared to particularly benefit patients with CH in CANTOS (Cardiovascular Risk Reduction Study [Reduction in Recurrent Major CV Disease Events]). is an epigenetic modifier that decreases promoter methylation.

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Clonal hematopoiesis (CH) increases the risk of atherosclerotic cardiovascular disease possibly due to increased plaque inflammation. Human studies suggest that limitation of interleukin-6 (IL-6) signaling could be beneficial in people with large CH clones, particularly in CH. Here we show that IL-6 receptor antibody treatment reverses the atherosclerosis promoted by CH, with reduction of monocytosis, lesional macrophage burden and macrophage colony-stimulating factor 1 receptor (CSF1R) expression.

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In a recent study, Martin-Rufino and colleagues combined massively parallel base editing in primary human hematopoietic stem and progenitor cells (HSPCs) with functional and single-cell transcriptomic readouts. A series of proof-of-principle experiments highlight the breadth of applications made possible with this approach, which range from gene therapy and immunotherapy, to characterizing single nucleotide variants.

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We report our clinical experience with the external oblique intercostal block in three consecutive adult patients who underwent liver surgery for resection of metastases. Enhanced recovery guidelines for liver surgery recommend intrathecal opioids and peripheral regional anaesthetic techniques in the context of multimodal analgesia to achieve adequate postoperative analgesia and early functional recovery. However, both laparoscopic and open approaches to liver surgery involve incisions in the upper abdomen, an anatomical area not well covered by previously described peripheral regional anaesthetic techniques.

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Unlabelled: The reprogramming of human acute myeloid leukemia (AML) cells into induced pluripotent stem cell (iPSC) lines could provide new faithful genetic models of AML, but is currently hindered by low success rates and uncertainty about whether iPSC-derived cells resemble their primary counterparts. Here we developed a reprogramming method tailored to cancer cells, with which we generated iPSCs from 15 patients representing all major genetic groups of AML. These AML-iPSCs retain genetic fidelity and produce transplantable hematopoietic cells with hallmark phenotypic leukemic features.

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This paper examines the spillover effects transmission mechanism between oil prices, oil price uncertainty and oil price volatility on labour market in Greece, using static and dynamic quantile connectedness methodology (Diebold and Yilmaz Diebold and Yilmaz, Int J Forecast 28:57-66, 2012; Ando et al. Ando T, Greenwood-Nimmo N, Shin Y (2018) 'Quantile connectedness: Modelling tail behavior in the topology of financial networks', Working Paper. https://ssrn.

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Hepatectomy-induced coagulation disturbances have been well studied over the past decade. Cumulative evidence supports the superiority of global coagulation analysis compared with conventional coagulation tests (i.e.

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In this issue of Cell Stem Cell, Reilly et al. propose loss of LMNB1, the gene encoding lamin B1, often deleted in MDS/AML, as a novel genetic basis for the abnormal nuclear shape of neutrophils (known as acquired Pelger-Huët anomaly) and a cause of HSPC fate alterations promoting malignancy.

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SF3B1K700E is the most frequent mutation in myelodysplastic syndrome (MDS), but the mechanisms by which it drives MDS pathogenesis remain unclear. We derived a panel of 18 genetically matched SF3B1K700E- and SF3B1WT-induced pluripotent stem cell (iPSC) lines from patients with MDS with ring sideroblasts (MDS-RS) harboring isolated SF3B1K700E mutations and performed RNA and ATAC sequencing in purified CD34+/CD45+ hematopoietic stem/progenitor cells (HSPCs) derived from them. We developed a novel computational framework integrating splicing with transcript usage and gene expression analyses and derived a SF3B1K700E splicing signature consisting of 59 splicing events linked to 34 genes, which associates with the SF3B1 mutational status of primary MDS patient cells.

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Despite the initial success of some drugs and vaccines targeting COVID-19, understanding the mechanism underlying SARS-CoV-2 disease pathogenesis remains crucial for the development of further approaches to treatment. Some patients with severe Covid-19 experience a cytokine storm and display evidence of inflammasome activation leading to increased levels of IL-1β and IL-18; however, other reports have suggested reduced inflammatory responses to Sars-Cov-2. In this study we have examined the effects of the Sars-Cov-2 envelope (E) protein, a virulence factor in coronaviruses, on inflammasome activation and pulmonary inflammation.

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Background: LNK/SH2B3 inhibits Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling by hematopoietic cytokine receptors. Genome-wide association studies have shown association of a common single nucleotide polymorphism in (R262W, T allele) with neutrophilia, thrombocytosis, and coronary artery disease. We have shown that ) reduces LNK function and that LNK-deficient mice display prominent platelet-neutrophil aggregates, accelerated atherosclerosis, and thrombosis.

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Background: COPD patients have an increased risk of cardiovascular disease and venous thromboembolism.

Methods: This study aimed to investigate whether patients with stable COPD have a prothrombotic state compared to COPD-free smokers. We conducted an observational study comparing levels of: D-dimers, INR, aPTT, coagulation factors; fibrinogen, FII, FV, FVII, FVIII, FIX, FX and coagulation inhibitors; protein S, proteins C and antithrombin between stable COPD patients and control subjects.

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Introduction: As the Coronavirus disease 2019 (COVID-19) pandemic is still ongoing with patients overwhelming healthcare facilities, we aimed to investigate the ability of white blood cell count (WBC) and their subsets, high fluorescence lymphocyte cells (HFLC), immature granulocyte count (IG), and C-reactive protein (CRP) to aid diagnosis of COVID-19 during the triage process and as indicators of disease progression to serious and critical condition.

Methods: We collected clinical and laboratory data of patients, suspected COVID-19 cases, admitted at the emergency department of University General Hospital of Ioannina (Ioannina, Greece). We selected 197 negative and 368 positive cases, confirmed by polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2.

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Unlabelled: Mutations in splicing factors (SF) are the predominant class of mutations in myelodysplastic syndrome (MDS), but convergent downstream disease drivers remain elusive. To identify common direct targets of missplicing by mutant U2AF1 and SRSF2, we performed RNA sequencing and enhanced version of the cross-linking and immunoprecipitation assay in human hematopoietic stem/progenitor cells derived from isogenic induced pluripotent stem cell (iPSC) models. Integrative analyses of alternative splicing and differential binding converged on a long isoform of GNAS (GNAS-L), promoted by both mutant factors.

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Acute myeloid leukemia (AML) is a clonal hematopoietic stem and progenitor cell malignancy characterized by poor clinical outcomes. Major histocompatibility complex class I polypeptide-related sequence A and B (MICA/B) are stress proteins expressed by cancer cells, and antibody-mediated inhibition of MICA/B shedding represents a novel approach to stimulate immunity against cancers. We found that the MICA/B antibody 7C6 potently inhibits the outgrowth of AML in 2 models in immunocompetent mice.

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Clonal haematopoiesis, which is highly prevalent in older individuals, arises from somatic mutations that endow a proliferative advantage to haematopoietic cells. Clonal haematopoiesis increases the risk of myocardial infarction and stroke independently of traditional risk factors. Among the common genetic variants that give rise to clonal haematopoiesis, the JAK2 (JAK2) mutation, which increases JAK-STAT signalling, occurs at a younger age and imparts the strongest risk of premature coronary heart disease.

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