Myeloproliferative neoplasms (MPN) are clonal hematopoietic stem cell diseases characterized by proliferation of one or more myeloid cell lineages in the bone marrow and increased mature and immature cells in peripheral blood. As the most important discovery in recent studies of MPN, JAk2V617F mutation is considered to closely relate with the pathogenesis of MPN. The mutated JAK2 lost self-inhibition, and then, the sustained activation leads to a series of disorders in downstream signal transduction pathways, eventually resulting in malignant cell proliferation. A variety of methods have been used in quantitative/qualitative detection of JAK2V617F mutation, and researches about JAK2V617F mutation and its clinical features have also made some progress. However, it must be noted that there are still some unsolved problems, such as the role of JAk2V617F mutation in pathogenesis of MPN needs further exploration, effective targeted therapy for JAK2 is a attractive topic, and the application of JAK2V617F mutation in disease diagnosis also requires a deep research. In this review, the latest progress from different aspects is summarized briefly, including JAK2 and JAK2V617F mutation, effects of JAK2V617F mutation on the pathogenesis, clinical correlation of JAK2V617F with MPN, and targeting therapy.
Humans ; Janus Kinase 2 ; genetics ; Mutation ; Myeloproliferative Disorders ; genetics ; pathology

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 overview of thrombosis in myeloproliferative neoplasms(MPN) patients, and to explore the risk factors of thrombosis at diagnosis and during follow-up. METHODS: The clinical data of 388 MPN patients treated in our hospital were collected. The patients were followed up by outpatient and phone. The risk factors of thrombosis were analyzed by statistical methods. RESULTS: Among 388 MPN patients, 161 patients (41.49%) showed thromboses at diagnosis or during follow-up. Among them, 92.55% were arterial thromboses, 146 cases (96.27%) were complicated with thromboses at diagnosis, and 36 cases (11.46%) showed newly thromboses or progression of previous thromboses among the 314 received full follow-up patients. Age (P＜0.001, HR:1.033, 95%CI:1.016-1.051), JAK2V617F mutation (P=0.037, HR:1.72, 95%CI: 1.033-2.862), hypertension (P＜0.001, HR:2.639, 95%CI:1.659-4.197) and hyperlipidemia (P＜0.001, HR:2.659, 95%CI:1.626-4.347) were the independent risk factors affecting thrombosis at diagnosis of the patients. During the follow-up, age (P=0.016, HR:1.032, 95%CI: 1.006-1.059) and previous thrombosis history (P=0.019, HR:2.194, 95%CI: 1.135-4.242) were the independent risk factors affecting the progression of thrombosis at different sites or on the basis of the previous thrombosis in the patients. CONCLUSION Patients with advanced age, JAK2V617F mutation or complicated with hypertension and hyperlipidemia shows a higher risk of thrombosis at diagnosis, while the patients with advanced age or previous thrombosis history shows a higher risk of progression of thrombosis during the follow-up.
Humans ; Myeloproliferative Disorders/genetics* ; Neoplasms ; Philadelphia Chromosome ; Risk Factors ; Thrombosis

microRNA (miRNA) are small non-coding RNA molecules of 19 - 25 nucleotides in a variety of eukaryotic systems, that control gene expression at the post-transcriptional level by degrading or translational repressing target messenger RNA (mRNA). Many studies have addressed the role of miRNA in normal hematopoiesis, giving an interpretative key to the aberrant expression observed in human hematological diseases. Here, the advances of main studies on the role of miRNA in normal hematopoiesis, and identify the association of miRNA with the development, progression of myeloproliferative diseases, including miRNA and lymphopoiesis, miRNA and erythropoiesis, miRNA and megakaryopoiesis, miRNA and myelopoiesis, miRNA and myeloproliferative neoplasm with positive BCR-ABL-chronic myeloid leukemia, miRNA and myeloproliferative neoplasm with negative PCR-ABL (PV.IME, ET), and so on are reviewed.
Gene Expression Regulation ; Hematopoiesis ; genetics ; Humans ; MicroRNAs ; genetics ; metabolism ; Myeloproliferative Disorders ; genetics ; metabolism ; RNA, Messenger ; genetics

This study was purposed to investigate the feasibility of high resolution melting (HRM) in the detection of JAK2V617F mutation in patients with myeloproliferative neoplasm (MPN). The 29 marrow samples randomly selected from patients with clinically diagnosed MPN from January 2008 to January 2011 were detected by HRM method. The results of HRM analysis were compared with that detected by allele specific polymerase chain reaction (AS-PCR) and DNA direct sequencing. The results showed that the JAK2V617F mutations were detected in 11 (37.9%, 11/29) cases by HRM, and its comparability with the direct sequencing result was 100%. While the consistency of AS-PCR with the direct sequencing was moderate (Kappa = 0.179, P = 0.316). It is concluded that the HRM analysis may be an optimal method for clinical screening of JAK2V617F mutation due to its simplicity and promptness with a high specificity.
Bone Marrow Neoplasms ; genetics ; Female ; Humans ; Janus Kinase 2 ; genetics ; Male ; Mutation ; Myeloproliferative Disorders ; genetics

The key molecular events in the pathogenesis of myeloproliferative disorders (MPD) have been poorly defined to date, except the case of chronic myeloid leukaemia with the associated rearranged gene bcr/abl. In recent years, a number of different studies described the detection of JAK2 V617F mutation in haematopoietic cells from polycythemia vera patients and other MPDs, which indicates that it plays an important role in the pathogenesis of MPDs. In this review, the JAK2 V617F point mutation and its detection methods, its clinical correlations with MPDs and other malignant hepatopathies were summarized.
Humans ; Janus Kinase 2 ; genetics ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; genetics ; Myeloproliferative Disorders ; genetics

OBJECTIVETo identify the MPL L391-V392ins12 spliceosome and analyze its frequencies in patients with myeloproliferative neoplasms (MPN).

METHODSMPL aberrant spliceosome was identified through reverse transcription polymerase chain reaction (RT-PCR)combined with cloning sequencing. The mutation of this spliceosome in 248 MPN patients and 200 normal people was determined by allele-specific polymerase chain reaction (AS-PCR).

RESULTSA novel aberrant spliceosome of MPL gene (MPL L391-V392ins12)was identified, i.e. 36 bp intron was retained between exon7 and exon8, and there were 12 amino acids (EGLKLLPADIPV)inserted. MPL L391-V392ins12 mutation was detected in 19 (7.66%)of the 248 patients with MPN, including 1 (1.92%) of 52 patients with PV, 14 (9.66%) of 145 with ET, and 4 (7.84%) of 51 with PMF. And the mutation was not detected in the group of 200 normal people.

CONCLUSIONMPL L391-V392ins12 spliceosome is an aberrant spliceosome present in the MPN. It can be detected in PV, ET and PMF, and more frequently in ET and PMF. This mutation may play an important role in the process of MPN.

Humans ; Mutation ; Myeloproliferative Disorders ; genetics ; Neoplasms ; genetics ; Polymerase Chain Reaction ; Receptors, Thrombopoietin ; genetics ; Spliceosomes

Humans ; Myeloproliferative Disorders ; genetics ; Receptor, Fibroblast Growth Factor, Type 1 ; genetics

Myeloproliferative neoplasms ( MPN ) is a class of clonal hematopoietic stem cell disease. Studies found that the JAK-STAT signaling pathway is closely related to the pathogenesis of MPN. The lymphocyte-specific adaptor protein (LNK) gene negatively regulates Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling and may play an important role in the pathogenesis of MPN. Especially in JAK2 mutation-negative MPN, LNK gene specific mutations may be the key to cause MPN subtypes. Certain single nucleotide polymorphism of LNK gene regulation of hematopoietic cells in different directions may also be important influence factors of MPN performance for different subtypes. LNK gene functional changes lead to abnormal activation of the JAK-STAT signaling pathway, and may be a new mechanism of MPN. In this review, the role of LNK gene in MPN pathogenesis is briefly summarized.
Humans ; Janus Kinases ; metabolism ; Mutation ; Myeloproliferative Disorders ; genetics ; Proteins ; genetics ; STAT Transcription Factors ; metabolism ; Signal Transduction

OBJECTIVETo explore the clinical and laboratory characteristics of myleodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) with PDGFRβ abnormalities.

METHODSChromosome specimens were prepared directly and/or short-time culture of bone marrow cells. Karyotyping was performed with R-binding technique. Fluorescence in situ hybridization (FISH) was performed using PDGFRβ, PDGFRα, FGFR1 break-apart probes and whole chromosome 5 and 12 painting probes, respectively. The expression of JAK2 V617F was measured with quantitative PCR.

RESULTSThe clinical and hematological findings of 27 patients were compatible with diagnosis of MDS/MPN. PDGFRβ rearrangement was detected in 4 patients with D-FISH, and 2 of which were confirmed as t(5;12) by chromosome painting. PDGFRα, FGFR1 and JAK2 V617F mutation were not detected in these 4 PDGFRβ positive MDS/MPN patients with.

CONCLUSIONSPDGFRβ gene rearrangement may be detected in some MDS/MPN patients. FISH is a convenient and reliable approach to detect PDGFRβ gene.

Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Myeloproliferative Disorders ; genetics ; Neoplasms ; Receptor, Platelet-Derived Growth Factor beta ; genetics