The clinical course of essential thrombocythemia (ET) is complicated with thrombosis which significantly impacts patients' mortality. Studies have identified JAK2V617F mutation as an independent risk factor for thrombosis. Circulating extracellular vesicles (EVs) were evaluated in several studies regarding myeloproliferative neoplasms and thrombosis as potential biomarkers. The present study investigates the relationship between JAK2V617F mutation and EVs levels in 119 ET patients. Our analyses revealed that JAK2V617F-positive patients are at a significantly increased risk of thrombosis within five years before the ET diagnosis (hazard ratio [95% CI]: 11.9 [1.7-83.7], P = 0.013), and that JAK2V617F mutation is an independent risk factor for thrombosis at ET diagnosis or during the follow-up (hazard ratio [95% CI]: 3.56 [1.47-8.62], P = 0.005). ET patients have higher levels of platelet-EVs, erythrocyte-EVs and procoagulant activity of EVs than the healthy population. Absolute and relative counts of platelet-EVs are increased in the presence of JAK2V617F mutation (P = 0.018, P = 0.024, respectively). In conclusion, our results support the role of JAK2V617F mutation in the pathogenesis of thrombosis in essential thrombocythemia through enhancing platelet activation.
Here, we present the first case of fibrinogen variant FGG c.8G>A. We investigated the behaviour of this mutated fibrinogen in blood coagulation using fibrin polymerization, fibrinolysis, fibrinopeptides release measurement, mass spectrometry (MS), and scanning electron microscopy (SEM). The case was identified by routine coagulation testing of a 34-year-old man diagnosed with thrombosis. Initial genetic analysis revealed a heterozygous mutation in exon 1 of the FGG gene encoding gamma chain signal peptide. Fibrin polymerization by thrombin and reptilase showed the normal formation of the fibrin clot. However, maximal absorbance within polymerization was lower and fibrinolysis had a longer degradation phase than healthy control. SEM revealed a significant difference in clot structure of the patient, and interestingly, MS detected several posttranslational oxidations of fibrinogen. The data suggest that the mutation FGG c.8G>A with the combination of the effect of posttranslational modifications causes a novel case of hypofibrinogenemia associated with thrombosis.
- MeSH
- afibrinogenemie * komplikace genetika MeSH
- dospělí MeSH
- fibrin metabolismus MeSH
- fibrinogen genetika metabolismus MeSH
- fibrinogeny abnormální * genetika metabolismus MeSH
- hemostatika * MeSH
- lidé MeSH
- oxidační stres MeSH
- posttranslační úpravy proteinů MeSH
- trombóza * komplikace genetika MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
Fibrinogen, an abundant plasma glycoprotein, is involved in the final stage of blood coagulation. Decreased fibrinogen levels, which may be caused by mutations, are manifested mainly in bleeding and thrombotic disorders. Clinically relevant mutations of fibrinogen are listed in the Human Fibrinogen Database. For the αC-connector (amino acids Aα240-410, nascent chain numbering), we have extended this database, with detailed descriptions of the clinical manifestations among members of reported families. This includes the specification of bleeding and thrombotic events and results of coagulation assays. Where available, the impact of a mutation on clotting and fibrinolysis is reported. The collected data show that the Human Fibrinogen Database reports considerably fewer missense and synonymous mutations than the general COSMIC and dbSNP databases. Homozygous nonsense or frameshift mutations in the αC-connector are responsible for most clinically relevant symptoms, while heterozygous mutations are often asymptomatic. Symptomatic subjects suffer from bleeding and, less frequently, from thrombotic events. Miscarriages within the first trimester and prolonged wound healing were reported in a few subjects. All mutations inducing thrombotic phenotypes are located at the identical positions within the consensus sequence of the tandem repeats.
Thrombosis is the most common complication in BCR-ABL1 negative myeloproliferative neoplasms (MPN) that significantly impacts patients' mortality. Generally, there is an agreement on risk factors that possibly contribute to the increased risk of thrombosis, including age, history of thrombosis, JAK2V617F mutation, and cardiovascular risk factors. This study retrospectively investigates MPN-related and patient-related variables in relation to the thrombosis occurrence in MPN. Our analyses show that JAK2V617F-mutated patients are at a significantly increased risk of thrombosis within five years before the MPN diagnosis point with a hazard ratio (HR) of 15.49 (p=0.006). In multivariate analyses, independent risk factors for thrombotic complications during the follow-up are history of thrombosis (HR=2.23, p=0.019), age over 60 years at diagnosis (HR=1.56, p=0.037), the presence of JAK2V617F mutation (HR=3.01, p=0.002), and tobacco smoking (HR=1.75, p=0.01). Our results support the multifactorial mechanism of thrombosis in MPN patients, which demands individual and complex management.
- MeSH
- Janus kinasa 2 genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- mutace MeSH
- nádory * MeSH
- retrospektivní studie MeSH
- rizikové faktory MeSH
- trombóza * genetika MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Inherited thrombophilias represent a concerning risk factor due to a proclivity to an aberrant clot formation. However, in patients with left ventricular assist device (LVAD), their impact on bleeding and thrombotic complications remains still poorly understood. The aim of the present study was to evaluate the effect of thrombophilic mutation directed anticoagulation therapy on adverse clinical outcomes in LVAD patients. MATERIALS AND METHODS: About 138 consecutive patients indicated for LVAD implant (HeartMate II, Abbott, Plymouth, USA) were prospectively screened for three major thrombophilic mutations: factor II (prothrombin), factor V Leiden, and homozygous methylenetetrahydrofolate reductase (MTHFR). Subsequently, discordant individualized anticoagulation targets of INR 2.5-3.0 in thrombophilia positive and INR 1.8-2.2 in negative patients were established; notably without anti-platelet agents given the center standard of care. RESULTS: Mean age was 50 ± 12.7 years, 83% male. Mean duration of support was 464.5 days (SD 482.9; SEM 41.1) and median of 310 days (IQR 162; 546). Full thrombophilia positive cohort analysis has not revealed any significant impact on event free survival. In contrast, detailed analysis of specific thrombophilias subsets has revealed Factor II prothrombin mutation as a significant predisposition for the pump thrombosis risk (SHR 10.48; p = 0.001) despite more aggressive prespecified anticoagulation target. Moreover, the incidence of bleeding events in prothrombin group was also significantly increased (SHR 6.0; p = 0.03). CONCLUSIONS: Our observations suggest that specific thrombophilias in LVAD patients may pose different intensity predisposition for thrombotic complications. Factor II (prothrombin) positive mutation was identified as significant risk factor associated with the pump thrombosis.
- MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- podpůrné srdeční systémy * škodlivé účinky MeSH
- prospektivní studie MeSH
- protrombin MeSH
- trombofilie * diagnóza genetika MeSH
- trombóza * genetika MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND/AIM: This work aimed to prospectively evaluate the clinical significance of circulating microparticles (MPs) in relation to thrombotic risk factors and thrombotic complications in patients with BCR/ABL1-negative myeloproliferative neoplasms (MPN). PATIENTS AND METHODS: In a cohort of 206 patients with MPN, MPs' procoagulant activity was measured by the Zymuphen functional assay in 429 samples, while platelet- and erythrocyte-MPs were enumerated by flow cytometry in 558 samples. RESULTS: MPN patients had higher MP levels than the control group. The levels of MPs were higher in male patients, smokers, and those who were older than 60 years, and in the presence of JAK2V617F mutation, history of thrombosis, platelets >400×109/l, hematocrit >45%, or leukocytes >10×109/l. Cytoreductive treatment reduced MP levels, with anagrelide being associated with lower MP levels than hydroxyurea. CONCLUSION: The relationship with thrombotic risk factors indicates a possible role of MPs in the complex thrombotic mechanism, though cytoreductive treatment seems to affect this role through reducing MP levels.
- MeSH
- lidé MeSH
- mikropartikule * MeSH
- myeloproliferativní poruchy * farmakoterapie genetika MeSH
- nádory * MeSH
- trombocyty MeSH
- trombóza * etiologie genetika MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- adherence k farmakoterapii psychologie MeSH
- antikoagulancia terapeutické užití MeSH
- dospělí MeSH
- heparin nízkomolekulární aplikace a dávkování MeSH
- inhibitory faktoru Xa krev MeSH
- komplikace těhotenství etiologie genetika patologie terapie MeSH
- lidé MeSH
- mutace MeSH
- progrese nemoci MeSH
- recidiva MeSH
- těhotenství MeSH
- trombofilie * etiologie genetika patologie terapie MeSH
- trombóza * etiologie genetika terapie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
Although it is well known that myeloproliferative neoplasms occur in younger patients, few large cohorts of such patients have been reported. Thus, our knowledge about circumstances of diagnosis, outcome and treatment is limited, especially for children and young adults. We therefore performed a systematic review of cases, published since 2005, concerning patients aged below 20 years at the time of diagnosis of essential thrombocythemia or polycythemia vera. We identified 396 cases of essential thrombocythemia and 75 of polycythemia vera. The median age at diagnosis was 9.3 and 12 years, respectively, and females constituted 57.6% and 45% of the groups, respectively. Half of the patients were asymptomatic at diagnosis. The proportion of so-called triple negativity was high: 57% in essential thrombocythemia and 73% in polycythemia vera. The incidence of thrombosis during the follow-up was 9.3% in patients with polycythemia vera and less, 3.8%, in those with essential thrombocythemia. Venous events were predominant (84.2%), with hemorrhagic episodes being rarer (<5%). The risk of evolution also seemed low (2% to myelofibrosis and no reports of acute leukemia), but the median follow-up was only 50 months. Survival curves were not available. Half of the patients received an antithrombotic drug and 40.5% received a cytoreductive drug. All data should be analyzed with care because of the proportion of missing data (10.7% to 74.7%). This review highlights interesting points concerning this population of young patients with myeloproliferative neoplasms, including that such patients were identified as negative for all common driver mutations, but also shows the need for larger contemporary cohorts with longer follow-up to assess the true prognosis of these patients.
- MeSH
- asymptomatické nemoci MeSH
- časná diagnóza MeSH
- cytotoxiny terapeutické užití MeSH
- dítě MeSH
- esenciální trombocytemie diagnóza farmakoterapie genetika patologie MeSH
- exprese genu MeSH
- fibrinolytika terapeutické užití MeSH
- Janus kinasa 1 genetika MeSH
- Janus kinasa 2 genetika MeSH
- krvácení diagnóza farmakoterapie genetika patologie MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mutace MeSH
- polycythaemia vera diagnóza farmakoterapie genetika patologie MeSH
- prognóza MeSH
- splenomegalie diagnóza farmakoterapie genetika patologie MeSH
- trombóza diagnóza farmakoterapie genetika patologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- Publikační typ
- časopisecké články MeSH
- systematický přehled MeSH
Induction of thrombosis in tumor vasculature represents an appealing strategy for combating cancer. Herein, we combined unique intrinsic coagulation properties of staphylocoagulase with new acquired functional potentials introduced by genetic engineering, to generate a novel bi-functional fusion protein consisting of truncated coagulase (tCoa) bearing an RGD motif on its C-terminus for cancer therapy. We demonstrated that free coagulase failed to elicit any significant thrombotic activity. Conversely, RGD delivery of coagulase retained coagulase activity and afforded favorable interaction of fusion proteins with prothrombin and αvβ3 endothelial cell receptors, as verified by in silico, in vitro, and in vivo experiments. Although free coagulase elicited robust coagulase activity in vitro, only targeted coagulase (tCoa-RGD) was capable of producing extensive thrombosis, and subsequent infarction and massive necrosis of CT26 mouse colon, 4T1 mouse mammary and SKOV3 human ovarian tumors in mice. Additionally, systemic injections of lower doses of tCoa-RGD produced striking tumor growth inhibition of CT26, 4T1 and SKOV3 solid tumors in animals. Altogether, the nontoxic nature, unique shortcut mechanism, minimal effective dose, wide therapeutic window, efficient induction of thrombosis, local effects and susceptibility of human blood to coagulase suggest tCoa-RGD fusion proteins as a novel and promising anticancer therapy for human trials.
- MeSH
- bakteriální proteiny genetika metabolismus MeSH
- infarkt patologie MeSH
- koagulasa genetika metabolismus MeSH
- kultivované buňky MeSH
- lidé MeSH
- mutace MeSH
- myši inbrední C57BL MeSH
- myši nahé MeSH
- nádorové buněčné linie MeSH
- nádory genetika metabolismus terapie MeSH
- oligopeptidy genetika MeSH
- patologická angiogeneze genetika metabolismus patologie MeSH
- rekombinantní fúzní proteiny genetika metabolismus MeSH
- trombóza genetika metabolismus MeSH
- tumor burden genetika MeSH
- xenogenní modely - testy protinádorové aktivity metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Controversies still exist regarding definition of the thrombotic risks in Ph- (BCR/ABL1-) myeloproliferative disorders with thrombocythemia (MPD-T). Platelet counts at diagnosis are currently not taken as a risk factor of thrombosis. In our cohort of 1179 patients with MPD-T, prospectively registered for anagrelide treatment, we found that the median platelet count prior to the thrombotic event was significantly higher than at time points without any ensuing thrombosis (453 vs. 400 × 10(9)/L, P < 0.001), albeit higher platelet counts at diagnosis tended to be connected with fewer thrombotic events (in contrast to WBC counts at diagnosis). The JAK2(V617F) mutation predicted both arterial and venous events, while age >65 yr, hypertension, diabetes mellitus, smoking, elevated triglyceride and homocysteine levels predicted arterial events only. For venous events, the specific thrombophilic risk factors (factor V 'Leiden' and others), antiphospholipid antibodies, and elevated factor VIII levels played a major role. During anagrelide treatment (± aspirin), we documented a decrease in both venous (6.7-fold) and arterial events (1.8-fold), while bleeding (mostly minor events) increased twofold compared to history. Our results suggest that keeping platelet counts at low levels may be a meaningful therapeutic measure to prevent thrombosis, although their counts at diagnosis lack any prognostic value.
- MeSH
- Aspirin aplikace a dávkování MeSH
- bcr-abl fúzní proteiny MeSH
- chinazoliny aplikace a dávkování MeSH
- filadelfský chromozom * MeSH
- Janus kinasa 2 genetika MeSH
- lidé MeSH
- missense mutace MeSH
- počet trombocytů MeSH
- prospektivní studie MeSH
- registrace * MeSH
- rizikové faktory MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- substituce aminokyselin MeSH
- trombocytóza * krev komplikace farmakoterapie genetika MeSH
- trombóza * krev farmakoterapie etiologie genetika MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
