Somatic JAK2 mutations are the main molecular cause of the vast majority of polycythemia vera (PV) cases. According to a recent structural model, the prevalent acquired V617F mutation improves the stability of the JAK2 dimer, thereby enhancing the constitutive JAK2 kinase activity. Germline JAK2 mutations usually do not largely alter JAK2 signaling, although they may modulate the impact of V617F. We found an unusual germline JAK2 mutation L604F in homozygous form in a young PV patient, along with a low allele burden JAK2 V617F mutation, and in her apparently healthy sister. Their father with a PV-like disease had L604F in a heterozygous state, without V617F. The functional consequences of JAK2 L604Fmutation were compared with those induced by V617F in two different in vitro model systems: (i) HEK293T cells were transfected with plasmids for exogenous JAK2-GFP expression, and (ii) endogenous JAK2 modifications were introduced into HeLa cells using CRISPR/Cas9. Both mutations significantly increased JAK2 constitutive activity in transfected HEK293T cells. In the second model, JAK2 modification resulted in reduced total JAK2 protein levels. An important difference was also detected: as described previously, the effect of V617F on JAK2 kinase activity was abrogated in the absence of the aromatic residue F595. In contrast, JAK2 hyperactivation by L604F was only partially inhibited by the F595 change to alanine. We propose that the L604F mutation increases the probability of spontaneous JAK2 dimer formation, which is physiologically mediated by F595. In addition, L604F may contribute to dimer stabilization similarly to V617F.
- MeSH
- HEK293 buňky MeSH
- HeLa buňky MeSH
- Janus kinasa 2 genetika MeSH
- lidé MeSH
- mutace MeSH
- zárodečné buňky * MeSH
- zárodečné mutace * MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- akutní promyelocytární leukemie * diagnóza klasifikace terapie MeSH
- lidé MeSH
- protokoly protinádorové kombinované chemoterapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Arterial thrombosis is a common complication in patients with Ph- myeloproliferative neoplasms (MPN). We searched for the risk factors of stroke in MPN patients from anagrelide registry. We analyzed the potential risk factors triggering a stroke/TIA event in 249 MPN patients with previous stroke (n = 168) or Transient Ischemic Attack (TIA) (n = 140), and in 1,193 MPN control subjects (without clinical history of thrombosis). These patients were registered in a prospective manner, providing a follow-up period after Anagrelide treatment. The median age of the patients in the experimental group was of 56 years of age (ranging from 34-76) and of 53 years of age (ranging from 26-74) in the control group (p < 0.001). Using a multivariate model, we determined the following as risk factors: JAK2V617F mutation (OR 2.106, 1.458-3.043, p = 0.006), age (OR 1.017/year, 1.005-1,029, p = 0.006), male gender (OR 1.419, 1.057-1.903, p = 0.020), MPN diagnosis (OR for PMF 0.649, 0.446-0.944, p = 0.024), BMI (OR 0.687 for BMI > 25, 0.473-0.999, p = 0.05) and high TAG levels (OR 1.734, 1.162-2.586, p = 0.008), all of which were statistically significant for CMP development. Concerning the risk factors for thrombophilia, only the antiphospholipid syndrome (OR 1.994, 1.017-3.91, p = 0.048) was noteworthy in a stroke-relevant context. There was no significant difference between the blood count of the patients prior to a stroke event and the control group, both of which were under a cytoreductive treatment. We found that age, male gender, JAK2V617F mutation, previous venous thrombosis, and hypertriglyceridemia represent independent risk factors for the occurrence of a stroke in Ph- MPN patients.
- MeSH
- cévní mozková příhoda etiologie MeSH
- chinazoliny terapeutické užití MeSH
- dospělí MeSH
- fibrinolytika terapeutické užití MeSH
- Janus kinasa 2 genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- myeloproliferativní poruchy komplikace genetika MeSH
- rizikové faktory MeSH
- senioři MeSH
- trombóza etiologie prevence a kontrola MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
External quality assurance (EQA) programs are vital to ensure high quality and standardized results in molecular diagnostics. It is important that EQA for quantitative analysis takes into account the variation in methodology. Results cannot be expected to be more accurate than limits of the technology used, and it is essential to recognize factors causing substantial outlier results. The present study aimed to identify parameters of specific importance for JAK2 V617F quantification by quantitative PCR, using different starting materials, assays, and technical platforms. Sixteen samples were issued to participating laboratories in two EQA rounds. In the first round, 19 laboratories from 11 European countries analyzing JAK2 V617F as part of their routine diagnostics returned results from in-house assays. In the second round, 25 laboratories from 17 countries participated. Despite variations in starting material, assay set-up and instrumentation the laboratories were generally well aligned in the EQA program. However, EQA based on a single technology appears to be a valuable tool to achieve standardization of the quantification of JAK2 V617F allelic burden.
- MeSH
- Janus kinasa 2 genetika MeSH
- kvantitativní polymerázová řetězová reakce normy MeSH
- lidé MeSH
- missense mutace * MeSH
- molekulární patologie normy MeSH
- substituce aminokyselin MeSH
- zajištění kvality zdravotní péče * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky MeSH
- multicentrická studie MeSH
BACKGROUND: We retrospectively analyzed data from 310 patients with acute myeloid leukemia with intermediate-risk cytogenetics in first complete remission (CR1) to evaluate the usage and efficacy of various types of postremission therapy. PATIENTS AND METHODS: Cox regression with time-dependent covariates, landmark analysis, and competing risk models were used to estimate the outcomes and effects of treatment and patient- and disease-related risk factors. RESULTS: The early relapse rate and early nonrelapse mortality (NRM) were 12.8% and 4.4%, respectively. In our study, 77.2% of patients completed postremission therapy: 44% received allogeneic hematopoietic cell transplantation (HCT), 20% completed treatment with high-dose cytarabine (HIDAC), and 13% completed treatment with intermediate-dose cytarabine. The 3-year overall survival rate was 67.5% for patients treated with HIDAC and 63.4% after HCT (P = .5876). The NRM and relapse rate at 3 years were 0% and 58.9% after HIDAC and 21.9% and 29.3% after HCT, respectively. HCT reduced the risk of relapse (hazard ratio, 0.6; 95% confidence interval, 0.36-0.98). Total body irradiation-based myeloablative conditioning increased NRM compared with busulfan-based conditioning (hazard ratio, 8.33; 95% confidence interval, 2.52-27.45). CONCLUSION: Most patients with acute myeloid leukemia with intermediate-risk cytogenetics received allogeneic HCT, which decreased the risk of relapse but increased NRM, leading to a similar overall survival for patients who received HCT and HIDAC. Our data support the use of allogeneic transplantation for patients in CR1 from a human leukocyte antigen-matched related or unrelated donor after a busulfan-based myeloablative conditioning regimen as a primary strategy of postremission therapy for eligible younger patients.
- MeSH
- akutní nemoc MeSH
- celotělové ozáření MeSH
- cytarabin terapeutické užití MeSH
- dospělí MeSH
- hodnocení výsledků zdravotní péče metody statistika a číselné údaje MeSH
- homologní transplantace MeSH
- indukce remise MeSH
- kombinovaná terapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- myeloidní leukemie genetika patologie terapie MeSH
- přežití bez známek nemoci MeSH
- příprava pacienta k transplantaci metody MeSH
- proporcionální rizikové modely MeSH
- protinádorové antimetabolity terapeutické užití MeSH
- retrospektivní studie MeSH
- transplantace hematopoetických kmenových buněk metody MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Chronická lymfocytární leukemie (CLL) je onemocnění s mimořádně různorodým klinickým průběhem. Diagnostiku a léčbu je nutno individualizovat s přihlédnutím k věku, celkovému stavu, přidruženým chorobám a cílům léčby. V posledních letech přibyly zásadní poznatky týkající se posouzení prognózy i léčby (význam mutací genu TP53, nové monoklonální protilátky, inhibitory drah B-buněčného receptoru a další). Česká skupina pro CLL, sekce České hematologické společnosti ČLS JEP, proto vytvořila tato aktualizovaná doporučení k usnadnění rozhodnování o diagnostických a léčebných postupech v klinické praxi. Doporučení se zakládají na důkladné analýze současné literatury a vycházejí z principů medicíny založené na důkazech.
Chronic lymphocytic leukaemia (CLL) has a remarkably heterogeneous clinical course. The diagnostic procedures and therapeutic interventions need to be individually tailored according to patient age, comorbidities and therapeutic aims. There have been important developments in prognostication and therapy during recent years (e. g., significance of TP53 mutations, introduction of novel monoclonal antibodies and B-cell receptor signalling inhibitors). Therefore, the Czech CLL Study Group, the working group of the Czech Society of Haematology developed these updated guidelines to facilitate the decision-making process for diagnostic and therapeutic procedures in daily practice. The guidelines are based on a comprehensive analysis of current literature and follow the principles of evidence-based medicine.
- MeSH
- chronická lymfatická leukemie * diagnóza terapie MeSH
- hodnocení výsledků zdravotní péče metody MeSH
- humanizované monoklonální protilátky terapeutické užití MeSH
- kombinovaná terapie MeSH
- lidé MeSH
- monoklonální protilátky terapeutické užití MeSH
- prognóza MeSH
- protinádorové látky terapeutické užití MeSH
- protokoly protinádorové kombinované chemoterapie MeSH
- recidiva MeSH
- reziduální nádor diagnóza MeSH
- stupeň závažnosti nemoci MeSH
- transplantace kmenových buněk MeSH
- výběr pacientů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- směrnice pro lékařskou praxi MeSH
The role of antiplatelet therapy as primary prophylaxis of thrombosis in low-risk essential thrombocythemia has not been studied in randomized clinical trials. We assessed the benefit/risk of low-dose aspirin in 433 patients with low-risk essential thrombocythemia (271 with a CALR mutation, 162 with a JAK2(V617F) mutation) who were on antiplatelet therapy or observation only. After a follow up of 2215 person-years free from cytoreduction, 25 thrombotic and 17 bleeding episodes were recorded. In CALR-mutated patients, antiplatelet therapy did not affect the risk of thrombosis but was associated with a higher incidence of bleeding (12.9 versus 1.8 episodes per 1000 patient-years, P=0.03). In JAK2(V617F)-mutated patients, low-dose aspirin was associated with a reduced incidence of venous thrombosis with no effect on the risk of bleeding. Coexistence of JAK2(V617F)-mutation and cardiovascular risk factors increased the risk of thrombosis, even after adjusting for treatment with low-dose aspirin (incidence rate ratio: 9.8; 95% confidence interval: 2.3-42.3; P=0.02). Time free from cytoreduction was significantly shorter in CALR-mutated patients with essential thrombocythemia than in JAK2(V617F)-mutated ones (median time 5 years and 9.8 years, respectively; P=0.0002) and cytoreduction was usually necessary to control extreme thrombocytosis. In conclusion, in patients with low-risk, CALR-mutated essential thrombocythemia, low-dose aspirin does not reduce the risk of thrombosis and may increase the risk of bleeding.
- MeSH
- čas zasáhnout při rozvinutí nemoci MeSH
- dítě MeSH
- dospělí MeSH
- esenciální trombocytemie komplikace diagnóza genetika MeSH
- fenotyp MeSH
- incidence MeSH
- inhibitory agregace trombocytů terapeutické užití MeSH
- Janus kinasa 2 genetika MeSH
- kalretikulin genetika MeSH
- krvácení epidemiologie etiologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mutace * MeSH
- počet leukocytů MeSH
- pozorné vyčkávání * MeSH
- trombóza epidemiologie etiologie prevence a kontrola MeSH
- výsledek terapie MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
