Acquired hemophilia A (AHA) is a rare disease resulting from autoantibodies (inhibitors) against endogenous factor VIII (FVIII) that leads to bleeding, which is often spontaneous and severe. AHA ...tends to occur in elderly patients with comorbidities and is associated with high mortality risk from underlying comorbidities, bleeding, or treatment complications. Treatment, which consists of hemostatic management and eradication of the inhibitors, can be challenging to manage.
Few data are available to guide the management of AHA‐related bleeding and eradication of the disease‐causing antibodies. Endorsed by the Hemostasis and Thrombosis Research Society of North America, an international panel of experts in AHA analyzed key questions, reviewed the literature, weighed the evidence and formed a consensus to update existing guidelines.
AHA is likely underdiagnosed and misdiagnosed in real‐world clinical practice. Recommendations for the management of AHA are summarized here based on the available data, integrated with the clinical experience of panel participants.
Venous and arterial thromboembolism are major complications of myeloproliferative neoplasms (MPNs), comprising polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). ...Global hemostasis assays, including thrombin generation assay (TGA), rotational thromboelastometry (ROTEM), and thromboelastography (TEG), have been proposed as biomarkers to assess the hypercoagulability and thrombotic risk stratification in MPNs. We performed a systematic literature review on the parameters of TGA, ROTEM, and TEG and their association with thrombotic events and treatment strategies in MPNs. Thirty-two studies (all cross-sectional) were included, which collectively enrolled 1,062 controls and 1,608 MPN patients. Among the 13 studies that reported arterial or venous thrombosis, the overall thrombosis rate was 13.8% with 6 splanchnic thromboses reported. Out of the 27 TGA studies, there was substantial heterogeneity in plasma preparation and trigger reagents employed in laboratory assays. There was a trend toward increased peak height among all MPN cohorts versus controls and higher endogenous thrombin potential (ETP) between ET patients versus controls. There was an overall trend toward lower ETP between PV and PMF patients versus. controls. There were no substantial differences in ETP between JAK2-positive versus JAK2-negative MPNs, prior history versus negative history of thrombotic events, and among different treatment strategies. Of the three ROTEM studies, there was a trend toward higher maximum clot firmness and shorter clot formation times for all MPNs versus controls. The three TEG studies had mixed results. We conclude that the ability of parameters from global hemostasis assays to predict for hypercoagulability events in MPN patients is inconsistent and inconclusive. Further prospective longitudinal studies are needed to validate these biomarker tools so that thrombotic potential could be utilized as a primary endpoint of such studies.
Acquired haemophilia is a potentially life‐threatening bleeding disorder caused by the development of autoantibodies against coagulation factors, most commonly against factor (F) VIII (acquired ...haemophilia A; AHA). In around half of patients, an underlying disorder is associated with AHA; the remaining cases are idiopathic. Typically, the disorder presents with bleeding, ranging from mild to life‐ and limb‐threatening, in patients with no personal or family bleeding history. Diagnosis involves an isolated prolongation of the activated partial thromboplastin time, without correction in mixing studies, low FVIII activity levels and evidence of a FVIII inhibitor. As AHA is rare, a lack of familiarity of the condition may result in delayed diagnosis, and prompt haemostatic control is required to reduce morbidity and mortality. Bypassing agents (recombinant activated factor VII or activated prothrombin complex concentrates) can be used to control acute bleeding, and immunosuppression is necessary to eradicate the inhibitor. As clinical trials in this rare and heterogeneous disease are difficult, current evidence comes from observational studies, including registries. This review will focus on the diagnostic and therapeutic challenges of AHA and summarise how understanding of this complex condition has increased based on recent registry data.
Molecularly defined subclassification is associated with phenotypic malignancy of glioblastoma (GBM). However, current understanding of the molecular basis of subclass conversion that is often ...involved in GBM recurrence remain rudimentary at best. Here we report that canonical Wnt signalling that is active in proneural (PN) but inactive in mesenchymal (MES) GBM, along with miR-125b and miR-20b that are expressed at high levels in PN compared with MES GBM, comprise a regulatory circuit involving TCF4-miR-125b/miR-20b-FZD6. FZD6 acts as a negative regulator of this circuit by activating CaMKII-TAK1-NLK signalling, which, in turn, attenuates Wnt pathway activity while promoting STAT3 and NF-κB signalling that are important regulators of the MES-associated phenotype. These findings are confirmed by targeting differentially enriched pathways in PN versus MES GBM that results in inhibition of distinct GBM subtypes. Correlative expressions of the components of this circuit are prognostic relevant for clinical GBM. Our findings provide insights for understanding GBM pathogenesis and for improving treatment of GBM.
ATG4B stimulates autophagy by promoting autophagosome formation through reversible modification of ATG8. We identify ATG4B as a substrate of mammalian sterile20-like kinase (STK) 26/MST4. MST4 ...phosphorylates ATG4B at serine residue 383, which stimulates ATG4B activity and increases autophagic flux. Inhibition of MST4 or ATG4B activities using genetic approaches or an inhibitor of ATG4B suppresses autophagy and the tumorigenicity of glioblastoma (GBM) cells. Furthermore, radiation induces MST4 expression, ATG4B phosphorylation, and autophagy. Inhibiting ATG4B in combination with radiotherapy in treating mice with intracranial GBM xenograft markedly slows tumor growth and provides a significant survival benefit. Our work describes an MST4-ATG4B signaling axis that influences GBM autophagy and malignancy, and whose therapeutic targeting enhances the anti-tumor effects of radiotherapy.
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•MST4 kinase regulates the growth, sphere formation, and tumorigenicity of GBM cells•MST4 stimulates autophagy by activating ATG4B through phosphorylation of ATG4B S383•Radiation increases MST4 expression and ATG4B phosphorylation, inducing autophagy•Inhibiting ATG4B enhances the anti-tumor effects of radiotherapy in GBM PDX models
Huang et al. show that radiation induces MST4 expression and that MST4 phosphorylates ATG4B at serine 383, which increases ATG4B activity and autophagic flux. Inhibition of ATG4B reduces autophagy and tumorigenicity of glioblastoma (GBM) cells and improves the impact of radiotherapy on GBM growth in mice.
Emicizumab: the hemophilia A game-changer Alcedo Andrade, Pedro E; Mannucci, Pier Mannuccio; Kessler, Craig M
Haematologica (Roma),
05/2024, Letnik:
109, Številka:
5
Journal Article
Recenzirano
Odprti dostop
In hemophilia, the unmet needs regarding adherence to prophylaxis and lack of effective long-term prophylaxis regimens, especially in patients with inhibitors, led to the production of emicizumab, ...the first non-factor medicine for subcutaneous administration in patients with severe and moderate hemophilia A with or without factor VIII inhibitors. This review describes the research steps behind the development of this game-changing medication as well as its success in the prophylaxis of bleeding episodes, as witnessed by the results of pivotal clinical trials but also by real-life use in the frame of a still expanding global market. We also discuss potential and actual adverse events and the nuances related to clinical use, such as laboratory monitoring, development of neutralizing antidrug antibodies, risk of thrombosis/hypercoagulability and role in the management of surgical operations. The potential of emicizumab to prevent bleeding in other congenital and acquired coagulation disorders is also outlined.
Stimulation of platelet production by thrombopoietin-receptor agonists (TPO-RAs) is an effective second-line treatment in immune thrombocytopenia (ITP). This 28-day phase 2 study assigned subjects ...with ITP of ≥3 months to once-daily oral avatrombopag (2.5, 5, 10, or 20 mg), an investigational nonpeptide TPO-RA active in humans, or placebo; subjects completing randomized treatment could enroll in a 24-week extension study. Of 64 randomized subjects, 13% (avatrombopag 2.5 mg), 53% (5 mg), 50% (10 mg), and 80% (20 mg), vs 0% for placebo, achieved a platelet count (PC) response of ≥50 × 109/L with ≥20 × 109/L increase above baseline at day 28. Fifty-three subjects (83%) entered the extension: 52% and 76% had a durable (PC response at ≥75% of their platelet assessments over the last 14 weeks) and overall (stable response or response at any ≥2 consecutive visits) response, respectively. All subjects experienced ≥1 adverse event (AE) (most commonly fatigue, headache, and epistaxis); 19% (n = 12) reported ≥1 serious AE; 10 (16%) withdrew due to an AE (5 due to increased PC). Avatrombopag was active and generally well tolerated, with PC response rates and AE incidence comparable with other TPO-RAs. These studies were registered at www.clinicaltrials.gov as #NCT00441090 and #NCT00625443.
•Once-daily oral avatrombopag dose-dependently raised PCs over 28 days, with stable counts maintained over a 24-week extension.•Low rates of severe AEs and study drug discontinuations due to AEs occurred despite dose increases in maintenance.
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