OBJECTIVETo investigate the frequency and clinical implication of JAK2 mutation in patients with myeloproliferative neoplasm(MPN)and the correlation between the mutation and thrombosis.

METHODSThe clinical and laboratory data of 107 MPN patients was retrospectively analyzed. JAK2 mutation were detected with allele-specific polymerase chain reaction (AS-PCR) and sequencing. The significance of the mutation in disease diagnosis and molecular pathogenesis and the correlation between the mutation and thrombosis was analysed.

RESULTSJAK2 mutation was detected in 71 (66.4%) and thrombosis in 34 (31.8%) of the 107 MPN patients. Thrombosis occurred in 34.8% (16/46) of polycythemia vera (PV), 32.6% (14/43) of essential thrombocythemia (ET), and 22.2% (4/18) of primany myelofibrosis (PMF) patients. The difference among the 3 groups was not significant (χ(2) = 0.96, P > 0.05). The frequency of thrombosis in JAK2(+) MPN patients (82.4%, 28/34) was higher than that in JAK2(-) MPN patients (17.6%, 6/34) (χ(2) = 5.71, P < 0.05). The frequency of thrombosis in MPN patients > 60 years was higher (41.5%, 27/65) than that in patients < 60 years (16.7%, 7/42) (χ(2) = 7.28, P < 0.01).

CONCLUSIONJAK2 V617F mutation occurs in significant percentage of Chinese patients with MPN. Patients with JAK2 mutation and older age are more succeptible to thrombosis. JAK2 mutation screening in patients with unknown thrombosis is helpful to reveal the underlying latent-MPN.

Humans ; Mutation ; Myeloproliferative Disorders ; genetics ; Neoplasms ; Thrombocythemia, Essential ; genetics ; Thrombosis

OBJECTIVE: To investigate the clinical characteristics of essential thrombocytopenia (ET) patients with positive mutations including JAK2, CALR, MPL, or negative mutations. METHODS: A total of 66 newly diagnosed ET cases from January 2016 to December 2018 in Department of Hematology, Huaian No.1 People's Hospital affiliated to Nanjing Medical University were analyzed. Statistical analysis data included the patient's sex, age, symptoms, thrombosis and embolism events, spleen omegaly, platelet count (Plt), leukocyte (WBC) count, hemoglobin (Hb), fibrinogen (FIB), thrombus elastic diagram (TEG), serum potassium, blood glucose (GLU), lactate dehydrogenase (LDH), JAK2, CALR and MPL mutations, treatment options, and efficacy. RESULTS: All the patients were not MPL-positive, and divided in three groups: JAK2 mutation (46 cases, 69.7%), CALR mutation (9 cases, 13.6%) and gene negative mutation (11 cases, 16.7%) group. The average age of patients in the JAK2 mutation group was 63.2 years old, and significantly higher than that in the CALR mutation group (51.8 year) and gene negative group (50.2 year) (P＜0.05). Compared with the JAK2 mutation group and gene negative group, the CALR mutation group had lower WBC count (6.3×10/L vs 13.79×10/L) (P=0.003) (6.3×10/L vs 9.70×10/L) (P=0.009). Also the Hb level of patients in CALR mutation group was lower than the JAK2 mutation group (121.22 g/L vs 136.2 g/L) (P=0.036). However, there was higher tumor burden in the CALR mutation group, compared with the gene negative mutation group (300.11 U/L vs 227.4 U/L) (P=0. 033). There was no significant difference among the three groups, such as the Plt counts, serum potassium level, GLU level and FIB level (P＞0.05). In addition, thrombus and embolism appeared in 30.3% (20/66) cases. 18.2% (12/66) cases were complicated with hyperkalemia, which significantly correlated with Plt counts (r=0.518). TEG was performed in 34 patients, of which 41.2% (14/34) had abnormal TEG and 55.9% (19/34) were accompanied by Plt count ＞ 1 000 ×10/L, but there was no significant correlation between them (r=0.134). After routine clinical treatment, all the 66 cases achieved partial or complete hematological remission, but the disease usually repeated. Until now 4.5% (3/66) cases had been converted to myelofibrosis (MF) all with JAK2 mutation, but without advancing to acute myeloid leukemia. CONCLUSION ET patients with JAK2 mutation have higher incidence, moreover were in older age. However, the patients with CALR mutations display lower WBC count and Hb level, but higher tumor burden. In short, the multiple gene mutations of ET showed different clinical features closely relates with the prognosis, thus providing guidance for the clinical diagnosis and treatment.
Aged ; Calreticulin ; genetics ; Humans ; Janus Kinase 2 ; genetics ; Middle Aged ; Mutation ; Primary Myelofibrosis ; Thrombocythemia, Essential ; Thrombocytopenia

OBJECTIVE: To detect the levels of microparticles (MP) in plasma of patients with esseutial thrombo-cythermia(ET) and analyze the relationship between the JAK2V617F mutant and MP in ET patients. METHODS: The numerical values of MPs were analysed by using flow cytometry. Venous blood of 56 ET patients and 28 healthy persons was collected in the morning and anticoagulated with sodium citrate (1∶9). The RMP, PMP, TF RESULTS: The detection results showed that the MP levels in ET group were higher than those in normal control group: RMP (157.2±304.9/μl vs 21.3±18.4/μl), PMP (1378.9±2454/μl vs 113.8±97.1/μl), TF CONCLUSION The numerical values of MP detected are more in ET patients than those in healthy controls. The number of MP is higher in patients with thrombus than that without thrombus, so do in patients with splenomegaly and without splenomegaly. Patients with JAK2V617F mutation show higher number of TF
Blood Platelets ; Cell-Derived Microparticles ; Endothelial Cells ; Humans ; Mutation ; Patients ; Thrombocythemia, Essential/genetics*

OBJECTIVE: To investigate the clinical characteristics, laboratorial and bone marrow pathological features of primary thrombocytopenia (ET) patients with different mutations of CALR, JAK2 and MPL genes. METHODS: The chinical data of 120 cases of ET in Jiangsu provincial people's hospital/ The First Affiliated Hospital of Nanjing Medical University from January 2015 to December 2017 were collected and analyzed, including 76 cases with JAK2 gene mutation, 40 cases with CALR gene mutation, 2 cases with MPL gene mutations, 2 cases without gene mutation. RESULTS: Among the ET patients, compared with the JAK2 gene mutation, CALR gene mutation showed statistically significant deareament of white blood cells and hemoglobin (P=0.001, P=0.01) and the male platelets in CALR group showed significant increament (P=0.04). Fourthermore, the average number of megakaryocytes and its cluster numbers in each hight power field of vision showed statistically significant decreament in CALR group as compared with JAK2 group (P=0.001, P=0.001), and thrombotic events in CALR group were signicantly lower than those in JAK2 group (7.5% vs 18.4%) (P=0.03). CONCLUSION Mutations of CALR, JAK2 have different clinical characteristics and blood pathological changes of Chinese ET patients, and their clinical significance is worth to explore.
Bone Marrow ; Calreticulin ; genetics ; China ; Humans ; Janus Kinase 2 ; genetics ; Male ; Mutation ; Receptors, Thrombopoietin ; genetics ; Thrombocythemia, Essential

Classical BCR/ABL fusion gene negative myeloproliferative neoplasms (MPN), including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF), are clonal hematopoietic malignancies sharing in common origin in a multipotential hematopoietic stem cell. The phenotypic variability of the three entities can not be elucidated by JAK2V617F mutation only. Recent discoveries indicated that JAK2V617F allele burden, other mutated genes (such as TET2, ASXL1) and inherited predisposition can play roles in the complicated pathogenesis of MPN, which are summarized in this review.
Bone Marrow Neoplasms ; genetics ; Genetic Predisposition to Disease ; Humans ; Janus Kinase 2 ; genetics ; Mutation ; Myeloproliferative Disorders ; genetics ; Polycythemia Vera ; genetics ; Primary Myelofibrosis ; genetics ; Thrombocythemia, Essential ; genetics

No abstract available.
Female ; Fusion Proteins, bcr-abl/*genetics ; Humans ; Male ; Middle Aged ; Mutation ; Myeloproliferative Disorders/*genetics ; Polycythemia Vera/genetics ; Primary Myelofibrosis/genetics ; Proteins/*genetics ; Thrombocythemia, Essential/genetics

The morbidity and mortality of myeloproliferative neoplasms (MPNs) are primarily caused by arterial and venous complications, progression to myelofibrosis, and transformation to acute leukemia. However, identifying molecular-based biomarkers for risk stratification of patients with MPNs remains a challenge. We have previously shown that interferon regulatory factor-8 (IRF8) and IRF4 serve as tumor suppressors in myeloid cells. In this study, we evaluated the expression of IRF4 and IRF8 and the JAK2V617F mutant allele burden in patients with MPNs. Patients with decreased IRF4 expression were correlated with a more developed MPN phenotype in myelofibrosis (MF) and secondary AML (sAML) transformed from MPNs versus essential thrombocythemia (ET). Negative correlations between the JAK2V617F allele burden and the expression of IRF8 (P < 0.05) and IRF4 (P < 0.001) and between white blood cell (WBC) count and IRF4 expression (P < 0.05) were found in ET patients. IRF8 expression was negatively correlated with the JAK2V617F allele burden (P < 0.05) in polycythemia vera patients. Complete response (CR), partial response (PR), and no response (NR) were observed in 67.5%,10%, and 22.5% of ET patients treated with hydroxyurea (HU), respectively, in 12 months. At 3 months, patients in the CR group showed high IRF4 and IRF8 expression compared with patients in the PR and NR groups. In the 12-month therapy period, low IRF4 and IRF8 expression were independently associated with the unfavorable response to HU and high WBC count. Our data indicate that the expression of IRF4 and IRF8 was associated with the MPN phenotype, which may serve as biomarkers for the response to HU in ET.
Biomarkers ; Humans ; Hydroxyurea/therapeutic use* ; Interferon Regulatory Factors/genetics* ; Janus Kinase 2/genetics* ; Leukemia, Myeloid, Acute/genetics* ; Mutation ; Phenotype ; Primary Myelofibrosis/genetics* ; Thrombocythemia, Essential/genetics*

OBJECTIVE: To explore the relationship between clinical features, peripheral blood cell count, coagulation function, gene mutation and hemorrhagic events and thrombotic events in essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis(PMF) patients. METHODS: Clinical data of 78 patients with ET, PV, and PMF who were admitted to the Second Affiliated Hospital of Chongqing Medical University between September 2019 and August 2020 were retrospectively analyzed. Information about sex, age, gene mutation, peripheral blood cell count, coagulation function, and hemorrhagic and thrombotic events was included, and the influence of these data on the occurrence of hemorrhagic and thrombotic events was estimated. RESULTS: Among the 78 patients with myeloproliferative neoplasms, there were 47 cases of ET, 15 cases of PV, and 16 cases of PMF.A total of 10 patients (12.82%) experienced hemorrhagic events and 27 (34.62%) experienced thrombotic events. Male,patients aged ≥ 60 years, and patients with a JAK2V617F mutation were more likely to experience thrombotic events (P<0.05). Patients with thrombotic events had higher platelet (PLT) counts and fibrinogen (FIB) levels than patients without hemorrhagic-thrombotic events (P<0.05).White blood cell (WBC) count, red blood cell (RBC) count, hemoglobin (HGB) level, prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and international normalized ratio (INR) showed no statistical difference between patients with thrombotic events and patients without hemorrhagic-thrombotic events (P>0.05). There was also no significant difference in the above-mentioned indexes between patients with hemorrhagic events and patients without hemorrhagic-thrombotic events (P>0.05). Among JAK2V617F positive myeloproliferative neoplasm patients, male patients were more likely to have thrombotic events (P<0.05), and patients with thrombotic events had higher platelet counts than those without hemorrhagic-thrombotic events (P<0.05). There was no significant difference in age, white blood cell count, red blood cell count, hemoglobin level, PT, APTT, FIB, TT or INR between patients with thrombotic events and patients without hemorrhagic-thrombotic events (P>0.05). CONCLUSION Sex, age, JAK2V617F mutation and platelet count have a certain value for predicting thrombosis in patients with myeloproliferative neoplasms.
Hemoglobins/genetics* ; Hemorrhage ; Humans ; Janus Kinase 2/genetics* ; Male ; Mutation ; Myeloproliferative Disorders/genetics* ; Polycythemia Vera/genetics* ; Retrospective Studies ; Thrombocythemia, Essential ; Thrombosis

Coexistence of chronic lymphocytic leukemia (CLL) and essential thrombocythemia (ET) in a patient is extremely rare, with only 10 cases reported thus far in literature. This paper describes a 94-year-old male having atypical B-CLL with CD5⁻ (CD5⁻) phenotype and ET. In this patient, we performed interphase fluorescence in situ hybridization (FISH) analysis which revealed 13q14.3 deletion in 31% of B-lymphocyte nuclei and RB1 deletion in 27% of B-lymphocyte nuclei, but not in neutrophils and T-lymphocytes. Furthermore, we identified JAK2 V617F mutation in the peripheral blood nucleated cells and neutrophils, but not in the B- and T-lymphocyte populations. Therefore, it was concluded that the occurrence of CD5− B-CLL and ET in this patient was pathogenically independent.
Aged, 80 and over ; CD5 Antigens ; metabolism ; Humans ; In Situ Hybridization ; Janus Kinase 2 ; genetics ; Leukemia, Lymphocytic, Chronic, B-Cell ; genetics ; metabolism ; Male ; Mutation ; Thrombocythemia, Essential ; genetics ; metabolism

OBJECTIVETo compare the morphologic features of bone marrow (BM) between the prefibrotic-early primary myelofibrosis (PMF) and essential thrombocythaemia (ET).

METHODSeven cases of prefibrotic-early PMF were selected and analyzed. Based on the diagnostic standard of prefibrotic-early PMF by WHO, BM aspirate smears, trephine biopsy sections and imprints of 156 uncertain ET cases conducted simultaneously were recruited into this study, the BM morphologic features between the prefibrotic-early PMF and ET groups were analyzed. The morphological difference in 22 cases of prefibrotic-early PMF and 27 ET were compared between the JAK2V617F mutation positive and negative groups.

RESULTSOf the 156 uncertain ET cases, it was reclassified 61 prefibrotic-early PMF (34 MF-0, 27 MF-1), 12 PMF and 83 ET. The platelet count and LDH level in MF-1 group were obviously higher than that of ET group (P < 0.05). The blast percentage of BM smear in MF-1 group was also higher than that of ET group (P < 0.05). As to BM section, cases with increased nucleated cells (granulocyte), compact megakaryocytic cluster, megakaryocyte near bone trabecula, cloud-like megakaryocyte, small bare nucleus of megakaryocyte and large ball-like megakaryocyte in MF-0 and MF-1 group were significantly higher than that of ET group (all P < 0.05), cases with megakaryocytic cluster of various size in MF-1 group were significantly higher than that of MF-0 and ET groups (P < 0.05). The JAK2V617F mutation rate in prefibrotic-early PMF and ET groups were 54.5% and 48.1%, respectively. Hb level in JAK2V617F mutation positive group was obviously higher than the negative group (P < 0.05), no special change with megakaryocytic morphology was found between the positive and negative groups.

CONCLUSIONMorphology of BM section, especially megakaryocytic morphologic characteristics are the main basis in distinguishing prefibrotic-early PMF from ET. The importance of morphologic index were megakaryocytic cluster with various size, cloud-like megakaryocyte, large ball-like megakaryocyte, increased nucleated cells (granulocyte), small bare nucleus, megakaryocyte near bone trabecula and compact megakaryocytic cluster in order. JAK2V617F mutation provides no specific effect on the megakaryocytic morphology.

Aged ; Bone Marrow ; pathology ; Bone Marrow Examination ; Female ; Humans ; Janus Kinase 2 ; genetics ; Male ; Megakaryocytes ; pathology ; Middle Aged ; Primary Myelofibrosis ; genetics ; pathology ; Thrombocythemia, Essential ; genetics ; pathology