Impact of Molecular Biology in Diagnosis, Prognosis, and Therapeutic Management of -Negative Myeloproliferative Neoplasm.

-negative myeloproliferative neoplasms (MPNs) include three major subgroups-polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF)-which are characterized by aberrant hematopoietic proliferation with an increased risk of leukemic transformation. Besides the driver mutations, which are , more than twenty additional mutations have been identified through the use of next-generation sequencing (NGS), which can be involved with pathways that regulate epigenetic modifications, RNA splicing, or DNA repair. The aim of this short review is to highlight the impact of molecular biology on the diagnosis, prognosis, and therapeutic management of patients with PV, ET, and PMF.

Two SERPINC1 variants affecting N-glycosylation of Asn224 cause severe thrombophilia not detected by functional assays.

Antithrombin deficiency, the most severe congenital thrombophilia, might be underestimated, as some pathogenic variants are not detected by routine functional methods. We have identified 2 new SERPINC1 variants, p.Glu227Lys and p.

Lipoprotein(a): Pathophysiology, measurement, indication and treatment in cardiovascular disease. A consensus statement from the Nouvelle Société Francophone d'Athérosclérose (NSFA).

Lipoprotein(a) is an apolipoprotein B100-containing low-density lipoprotein-like particle that is rich in cholesterol, and is associated with a second major protein, apolipoprotein(a). Apolipoprotein(a) possesses structural similarity to plasminogen but lacks fibrinolytic activity. As a consequence of its composite structure, lipoprotein(a) may: (1) elicit a prothrombotic/antifibrinolytic action favouring clot stability; and (2) enhance atherosclerosis progression via its propensity for retention in the arterial intima, with deposition of its cholesterol load at sites of plaque formation.

The EHA Research Roadmap: Blood Coagulation and Hemostatic Disorders.

n 2016, the European Hematology Association (EHA) published the EHA Roadmap for European Hematology Research aiming to highlight achievements in the diagnostics and treatment of blood disorders, and to better inform European policy makers and other stakeholders about the urgent clinical and scientific needs and priorities in the field of hematology. Each section was coordinated by 1-2 section editors who were leading international experts in the field. In the 5 years that have followed, advances in the field of hematology have been plentiful.

The aminosterol Claramine inhibits β-secretase 1-mediated insulin receptor cleavage.

The cleavage of the insulin receptor by β-secretase 1 (BACE1) in the liver increases during diabetes, which contributes to reduce insulin receptor levels and impair insulin signaling. However, the precise signaling events that lead to this increased cleavage are unclear. We showed that BACE1 cleaves the insulin receptor in the early secretory pathway.

SLC44A2 deficient mice have a reduced response in stenosis but not in hypercoagulability driven venous thrombosis.

Background: Genome wide association studies (GWAS) identified SLC44A2 as a novel susceptibility gene for venous thrombosis (VT) and previous work established that SLC44A2 contributed to clot formation upon vascular injury.

Objective: To further investigate the role of SLC44A2 in VT by utilizing SLC44A2 deficient mice (Slc44a2 ) in two representative disease models.

Methods: Mice were included in a hypercoagulability model driven by siRNA-mediated hepatic gene silencing of anticoagulants Serpinc1 (antithrombin) and Proc (protein C) and a flow restriction (stenosis) model induced by partial ligation of the inferior vena cava.

Common Risk Factors Add to Inherited Thrombophilia to Predict Venous Thromboembolism Risk in Families.

The clinical venous thromboembolism (VTE) pattern often shows wide heterogeneity within relatives of a VTE-affected family, although they carry the same thrombophilia defect. It is then mandatory to develop additional tools for assessing VTE risk in families with thrombophilia. This study aims to assess whether common environmental and genetic risk factors for VTE contribute to explain this heterogeneity.

Initial strides for invent-VTE: Towards global collaboration to accelerate clinical research in venous thromboembolism.

Venous thromboembolism (VTE) represents a major global burden of disease and requires collaborative efforts to conduct large, high-quality investigator-initiated and academically sponsored studies addressing the most relevant clinical questions. Owing to increasing regulatory requirements, the highly competitive nature of peer-reviewed funding and costs associated with conducting large, multinational clinical trials, completing practice-changing research constitutes a growing challenge for clinical investigators. As clinical trialists interested in VTE, we founded INVENT (International Network of Venous Thromboembolism Clinical Research Networks) in an effort to promote and accelerate patient-oriented, investigator-initiated, international collaborative research, to identify, prioritize and answer key clinical research questions for patients with VTE.

Benefit of Switching Dual Antiplatelet Therapy After Acute Coronary Syndrome According to On-Treatment Platelet Reactivity: The TOPIC-VASP Pre-Specified Analysis of the TOPIC Randomized Study.

Objectives: This study sought to evaluate the impact of initial platelet reactivity on the benefit of switched strategy.

Background: TOPIC (Timing Of Platelet Inhibition after acute Coronary Syndrome) study suggested that switched dual antiplatelet therapy (DAPT) could improve net clinical benefit after acute coronary syndrome by preventing bleeding.

Methods: Acute coronary syndrome patients, 1 month after coronary stenting and event free, were randomly assigned to aspirin and clopidogrel (switched DAPT) or continuation of drug regimen (unchanged DAPT).

Benefit of switching dual antiplatelet therapy after acute coronary syndrome: the TOPIC (timing of platelet inhibition after acute coronary syndrome) randomized study.

Aims: Newer P2Y12 blockers (prasugrel and ticagrelor) demonstrated significant ischaemic benefit over clopidogrel after acute coronary syndrome (ACS). However, both drugs are associated with an increase in bleeding complications. The objective of the present study was to evaluate the benefit of switching dual antiplatelet therapy (DAPT) from aspirin plus a newer P2Y12 blocker to aspirin plus clopidogrel 1 month after ACS.

Macrothrombocytopenia and dense granule deficiency associated with FLI1 variants: ultrastructural and pathogenic features.

Congenital macrothrombocytopenia is a family of rare diseases, of which a significant fraction remains to be genetically characterized. To analyze cases of unexplained thrombocytopenia, 27 individuals from a patient cohort of the Bleeding and Thrombosis Exploration Center of the University Hospital of Marseille were recruited for a high-throughput gene sequencing study. This strategy led to the identification of two novel variants (c.

Germline variants in ETV6 underlie reduced platelet formation, platelet dysfunction and increased levels of circulating CD34+ progenitors.

Variants in ETV6, which encodes a transcription repressor of the E26 transformation-specific family, have recently been reported to be responsible for inherited thrombocytopenia and hematologic malignancy. We sequenced the DNA from cases with unexplained dominant thrombocytopenia and identified six likely pathogenic variants in ETV6, of which five are novel. We observed low repressive activity of all tested ETV6 variants, and variants located in the E26 transformation-specific binding domain (encoding p.

Is platelet inhibition correlated with time from last intake on P2Y12 blockers after an acute coronary syndrome? A pilot study.

Delay from the last intake of drug could be an important and unexplored variable in the biological response to antiplatelet agents after acute coronary syndrome (ACS) discharge. The objective was to define the impact of the delay from P2Y12 blocker intake on the platelet inhibition level. We compared ticagrelor-, prasugrel-, and clopidogrel-treated patients.

Genetic determined low response to thienopyridines is associated with higher systemic inflammation in smokers.

Aim: To investigate whether the interactions of CYP2C19*2 and CYP2C19*17 with smoking are associated with the levels of P2Y12 receptor inhibition and CRP, in on-thienopyridine post-stenting patients.

Methods & Results: At 1-month follow-up, the interactions of smoking and CYP2C19 polymorphisms on the vasodilator-stimulated phosphoprotein - platelet reactivity index (VASP PRI), and CRP were explored in three metabolizing groups (1128 patients) as follow: poor metabolizers (*2 carriers/*17 noncarriers); intermediate metabolizers (*2 carriers/*17 carriers or *2 noncarriers/*17 noncarriers); and ultrarapidmetabolizers (*2 allele noncarriers/*17 carriers). The interactions of metabolizing status and smoking was significant for CRP (p = 0.

[Antiphospholipids antibodies and hemodialysis: a frequent association linked to arteriovenous fistula thrombosis].

Antiphospholipid antibodies (APL) are a heterogeneous family of auto-antibodies that recognize phospholipoproteins bound antigenic epitopes. APL prevalence in patients on chronic hemodialysis ranges from 11 to 37% in the literature. The association of APL with hemodialysis vascular access (VA) thrombosis has already been reported in small studies.

Human CalDAG-GEFI gene (RASGRP2) mutation affects platelet function and causes severe bleeding.

The nature of an inherited platelet disorder was investigated in three siblings affected by severe bleeding. Using whole-exome sequencing, we identified the culprit mutation (cG742T) in the RAS guanyl-releasing protein-2 (RASGRP2) gene coding for calcium- and DAG-regulated guanine exchange factor-1 (CalDAG-GEFI). Platelets from individuals carrying the mutation present a reduced ability to activate Rap1 and to perform proper αIIbβ3 integrin inside-out signaling.

Impact of obesity and the metabolic syndrome on response to clopidogrel or prasugrel and bleeding risk in patients treated after coronary stenting.

This study aimed to analyze the impact of body mass index (BMI) and the metabolic syndrome (MS) on responses to clopidogrel or prasugrel and bleeding risk after acute coronary syndrome. The study included 1,542 consecutive patients who underwent coronary stenting (287 clopidogrel 75 mg, 868 clopidogrel 150 mg, and 387 prasugrel 10 mg). Platelet reactivity was assessed 1 month after discharge using platelet reactivity index vasodilator stimulated phosphoprotein (PRI VASP).

Clinical implications of very low on-treatment platelet reactivity in patients treated with thienopyridine: the POBA study (predictor of bleedings with antiplatelet drugs).

Objectives: This study was designed to define the hyperresponse to thienopyridine (very low on-treatment platelet reactivity [VLTPR]) as the most predictive threshold value of platelet reactivity index vasodilator-stimulated phosphoprotein (PRI VASP) for the prediction of non-access site-related bleeding events. We also aimed to identify predictors of bleeding and VLTPR in patients treated with thienopyridines.

Background: New P2Y12 blockers and platelet monitoring has been proposed to optimize platelet inhibition after acute coronary syndromes and improve ischemic outcomes.