伴有JAK2 V617F突变的慢性中性粒细胞白血病1例并文献复习

目的:探讨伴有JAK2基因V617F突变的慢性中性粒细胞白血病(CNL)的实验室特征。方法:通过骨髓涂片进行细胞形态学分析诊断;采用实时荧光定量PCR方法检测BCR-ABL融合基因;实时荧光定量PCR方法及DNA测序方法检测JAK2 V617F突变;RHG显带进行常规染色体核型分析。结果:细胞形态学诊断为慢性中性粒细胞白血病;BCR/ABL融合基因为阴性;存在JAK2 V617F杂合突变;染色体分析结果为正常核型。结论:JAK2 V617F突变在慢性中性粒细胞白血病中很少见,具有该突变的CNL患者有较长的生存期,JAK2 V617F突变可能提示预后良好。     

伴有JAK2 V617F突变的慢性中性粒细胞白血病1例并文献复习

目的：探讨伴有JAK2基因V617F突变的慢性中性粒细胞白血病（CNL）的实验室特征。方法：通过骨髓涂片进行细胞形态学分析诊断;采用实时荧光定量PCR方法检测BCR-ABL融合基因;实时荧光定量PCR方法及DNA测序方法检测JAK2 V617F突变;RHG显带进行常规染色体核型分析。结果：细胞形态学诊断为慢性中性粒细胞白血病;BCR/ABL融合基因为阴性;存在JAK2 V617F杂合突变;染色体分析结果为正常核型。结论：JAK2 V617F突变在慢性中性粒细胞白血病中很少见,具有该突变的CNL患者有较长的生存期,JAK2 V617F突变可能提示预后良好。     

JAK2基因突变与慢性髓系白血病 易感性的meta 分析

目的：探讨JAK2基因突变与慢性髓系白血病（CML）的关系。方法：检索中国知网（CNKI）、维普（VIP）、万方、PubMed、Web of Science、CBM数据库中关于JAK2突变与CML关系的文章。检索时间截至2018年9月,由两位研究者独立按照纳入与排除标准筛选文献,提取资料后,用纽卡斯尔-渥太华量表（NOS）评分进行质量评价。采用Stata 11.0、RevMan 5.3软件进行meta分析。结果：共纳入15篇文章,包含总病例数1 684例,JAK2基因突变104例（突变位点分别位于第12和第14号外显子编码序列的第1 849位碱基G被T取代）。Meta分析结果显示CML患者的JAK2基因突变率为0.08[95% CI （0.05,0.11）],亚组分析显示费城染色体（Ph）和JAK2是否突变、不同地区的突变分布、外显子的突变位点是异质性的主要来源。结论：慢性髓系白血病细胞JAK2基因外显子12和14突变、突变体JAKV617F的存在可能促使CML的发生。     

亚砷酸对JAK2V617F阳性的骨髓增殖性肿瘤的影响

目的:探讨亚砷酸(arsenic trioxide,ATO)在治疗JAK2V617F突变阳性的骨髓增殖性疾病(myelopro-liferative neoplasm,MPN)中的作用。方法:选取20例JAK2V617F阳性的MPN患者用亚砷酸治疗,观察其治疗前后不同时期相应的血象变化以及JAK2V617F表达,并与单用羟基脲的对照组作比较。结果:与对照组相比,3个月及1年后,应用亚砷酸治疗组的红细胞、血红蛋白、血小板、白细胞均明显降低(P<0.01);治疗3年后两组上述指标无明显差异(P>0.05);JAK2V617F的转阴率两组无明显差异性(P>0.05)。结论:亚砷酸作为一种诱导凋亡剂短期内可以有效地降低三系血细胞,但未有证据表明能降低MPN患者JAK2V617F的阳性表达,故长期疗效需更多的临床及实验观察。     

JAK2 V617F mutation is uncommon in non-Hodgkin lymphomas

Recently, the JAK2 V617F mutation has been reported in high proportions of chronic myeloproliferative disorders, including polycythemia vera. To see whether the JAK2 V617F is important in the pathogenesis of lymphoid malignancies, this study analysed the occurrence of the JAK2 V617F mutation in 117 non-Hodgkin lymphomas (NHLs) by a single strand conformation polymorphism assay. However, there was no JAK2 V617F mutation in the NHLs and the data suggest that the JAK2 V617F mutation may not play a role in the development of NHL.     

费城染色体阴性骨髓增殖性肿瘤的诊断与治疗:JAK2 V617F基因突变评价

简要回顾了近百余年人们对骨髓增殖性肿瘤(MPN)的认识过程,重点讨论这一类疾病的诊断与治疗.JAK2 V617F基因突变的发现将费城染色体阴性(Ph-)MPN带入分子生物学时代,为临床提供了重要的诊断手段和依据,指导、研发了芦可替尼(ruxolitinib)等一批靶向药物.但是,与慢性粒细胞白血病(CML)中的bcr-abl不同,JAK2 V617F突变不是MPN诊断的“金标准”,其他辅助检查和鉴别诊断仍不可少.目前,JAK抑制剂开始用于Ph-MPN患者,有一定的适应证,远期疗效正在观察,目前还不能替代有效的常规治疗,如羟基脲、阿司匹林等.     

JAK2 V617F基因突变阳性骨髓增殖性肿瘤治疗研究进展

JAK2 V617F基因突变阳性骨髓增殖性肿瘤(MPN)由真性红细胞增多症(PV)、原发性血小板增多症(ET)和原发性骨髓纤维化(PMF)组成.文章聚焦于其危险度积分系统和治疗进展,包括一线及二线治疗、JAK2抑制剂、降细胞治疗、抗纤维化和其他单药或联合治疗.     

JAK2 V617F基因突变与血管栓塞性疾病的相关性研究

目的 探讨JAK2 V617F基因突变与血管栓塞性疾病的相关性,为临床诊治和预防栓塞提供依据.方法 以首都医科大学宣武医院神经内科、心脏科及血管外科收治的血红蛋白＞ 160g/L、血小板计数＞ 300×109/L的56例患者为研究对象,其中骨髓增殖性肿瘤患者47例.回顾性分析患者血管栓塞情况、JAK2 V617F突变情况及两者之间的相关性.结果 JAK2 V617F基因突变阳性率为37.50％(21/56),血管栓塞发生率为41.07％(23/56),两者之间存在关联性(P=0.014).结论 JAK2 V617F基因突变检测有助于骨髓增殖性肿瘤患者的早期诊断和治疗,减少栓塞并发症,提高患者生命质量.     

Suppression of multiple anti‐apoptotic BCL2 family proteins recapitulates the effects of JAK2 inhibitors in JAK2V617F driven myeloproliferative neoplasms

Several lines of research suggest that Bcl‐xL‐mediated anti‐apoptotic effects may contribute to the pathogenesis of myeloproliferative neoplasms driven by JAK2V617F and serve as therapeutic target. Here, we used a knock‐in JAK2V617F mouse model and confirmed that Bcl‐xL was overexpressed in erythroid progenitors. The myeloproliferative neoplasm (MPN)‐induced phenotype in the peripheral blood by conditional knock‐in of JAK2V617F was abrogated by conditional knockout of Bcl2l1, which presented anemia and thrombocytopenia independently of JAK2 mutation status. Mx1‐Cre Jak2V617^W/VF/Bcl2l1^f/f mice presented persistent splenomegaly as a result of extramedullary hematopoiesis and pro‐apoptotic stimuli in terminally differentiated erythroid progenitors. The pan‐BH3 mimetic inhibitor obatoclax showed superior cytotoxicity in JAK2V617F cell models, and reduced clonogenic capacity in ex vivo assay using Vav‐Cre Jak2V617F bone marrow cells. Both ruxolitinib and obatoclax significantly reduced spleen weights in a murine Jak2V617F MPN model but did not show additive effect. The tumor burden reduction was observed with either ruxolitinib or obatoclax in terminal differentiation stage neoplastic cells but not in myeloid‐erythroid precursors. Therefore, disrupting the BCL2 balance is not sufficient to treat MPN at the stem cell level, but it is certainly an additional option for controlling the critical myeloid expansion of the disease.     

骨髓增殖性肿瘤JAK2V617F基因突变与疾病临床特征相关性的分析※

 摘要：目的：研究我区骨髓增殖性肿瘤（MPN）中JAK2V617F基因突变与疾病临床特征的相关性。方法：回顾性分析我区134例MPN患者JAK2V617F基因突变与患者性别、年龄、民族、外周血白细胞、血小板计数、血红蛋白、血清乳酸脱氢酶（LDH）水平及是否合并血栓、出血及心血管疾病并发症等临床特征的相关性进行统计分析。结果：134例MPN患者中PV 51例,ET 66例,IMF17例,存在JAK2V617F突变98例（73.1%）。年龄60岁以上者发生突变率较60岁以下者明显增高（p＜0.05）,MPD患者中JAK2V617F突变阳性者外周血白细胞计数、血红蛋白水平与血栓、心血管疾病的发生率均高于突变阴性者（p＜0.05）,而性别、民族、血小板计数及LDH水平在JAK2V617F基因突变阳性与阴性患者间无显著性差异（p＞0.05）。结论：MPN患者JAK2V617F基因突变与MPN患者年龄、外周血白细胞计数、血红蛋白水平、血栓及心血管疾病并发症相关。     

Study of CALR,MPL, and c-kit Gene Mutations in Thai Patients with JAK2 V617F Negative Myeloproliferative Neoplasms

Objective: The aim of this study to determine the prevalence of CALR, MPL and c-kit gene mutations in JAK2 V617F negative-MPN patients. Methods: The retrospective study of CALR, MPL and c-kit mutations were analyzed in 113 samples collected from March 2010 to May 2017 and identified as JAK2 V617F–negative MPN Thai patients. The samples were analysis by gel electrophoresis and direct sequencing. Results: 28.3% of JAK2 V617F–negative MPN patients showed CALR gene mutations. Within the MPN patients with CALR mutation, 46.9% were classified as essential thrombocythemia (ET) and 20.9% were classified as primary myelofibrosis (PMF). Previous studies classified CALR mutations into three types using negatively charged amino acid stretches at the C-terminal domain. Type 1-like mutations were observed in 12 of 49 (24.5%) ET patients and type 2-like mutations were observed in 10 of 49 (20.4%) patients. In addition, 8 of 43 (18.6%) PMF patients showed type 1-like mutations and 1 of 43 (2.3%) showed type 2-like CALR mutation. Interestingly, platelet counts were higher in patients with CALR gene mutation than in patients without CALR gene mutation. MPL mutations (W515K and W515L) were identified in 2 of 109 (1.8%) MPN patients; the MPL mutations were only found in ET patients, which was consistent with previous studies. We did not detect exon 17 c-kit mutation in JAK2-negative MPN patients but detected intronic single nucleotide polymorphisms at c.74,978 and c.75,255 in these samples. Approximately 66% of patients did not have mutations in CALR and MPL genes, in addition to lacking JAK2 gene mutation, and these cases are classified as triple-mutations. Conclusion: Our results showed that 66% of cases were triple-negative mutation MPN because they lacked mutations in JAK2, CALR and MPL genes. The frequencies of CALR and MPL mutation in this study are similar to other CALR and MPL patient data.     

80例急性髓性白血病M2型患者JAK2V617F基因突变的检测及临床意义

目的 探讨JAK2V617F基因突变在急性髓性白血病M2型(AML-M2)患者中的发牛率和临床预后意义.方法 采用等位基因特异性聚合酶链反应(AS-PCR)技术,检测80例AML-M2患者的JAK2V617F基因突变情况.结果 80例AML-M2患者中,初诊时JAK2V617F基因突变6例,复发时JAK2V617F基因突变1例,JAK2V617F基因的突变率为8.8%.7例JAK2V617F基因突变者的血象和骨髓象均呈现出白血病改变特征,而无骨髓增殖性疾病(MPD)征象;免疫分型显示为髓系表达.接受治疗的5例JAK2V617F基因突变者中,有4例患者在治疗后达到完全缓解,1例未缓解;除1例失访外,其余4例患者的中位生存期为18.5个月.结论 JAK2V617F基因突变作为AML发病机制中的Ⅰ类突变,可能并不是AML发病的初始事件;初诊AML患者出现JAK2V617F基因突变也并不意味着疾病顸后较差.     

骨髓增殖性肿瘤研究进展:JAK2 V617F基因突变发现后10年

结合大量的临床实践和近10年来对骨髓增殖性肿瘤(MPN)[骨髓增殖性疾病(MPD)]在JAK2 V617F基因突变等分子水平的大量研究,更加深了对MPN(MPD)的分子发病机制和临床价值的认识.研究者们探讨了JAK2 V617F基因突变如何促进MPN(MPD)发病的机制,分析了JAK2 V617F基因突变的分子机制和JAK2 V617F基因突变如何引起MPN(MPD)不同临床表型,以及MPN(MPD)基因组突变图谱及其生物学意义,指出了MPN(MPD)病理克隆的复杂性.JAK2 V617F基因突变在研究和诊治MPN(MPD)的过程中发挥着重大作用,其促使MPN(MPD)的研究和应用深入到基因/分子水平,治疗更趋于靶向性,更加精确,特别是使那些常规检验无法明确诊断的患者获得了及时诊治,避免了合并疾病的发生.MPN(MPD)的防治焦点是及时诊治,预防并避免血栓/出血性并发症的发生.推荐首选干扰素α(IFN-α)治疗,对于年龄大于60岁的患者,羟基脲是可以采用的.MPN(MPD)患者的预后大多数良好,发生恶变的风险不高,这是反复建议对中国MPD患者避免使用MPN称谓的主要理由.     

骨髓增殖性肿瘤120例JAK2 V617F基因突变的临床分析

目的 探讨JAK2 V617F基因突变在骨髓增殖性肿瘤(MPN)患者中的发生率及临床意义.方法 采用骨髓细胞学和活组织检查方法分析120例患者的骨髓病理状况,监测费城染色体(Ph染色体)和bcr-abl融合基因.从患者骨髓抽提DNA,采用荧光定量PCR技术检测JAK2 V617F基因突变.结果 所有患者均呈现出MPN各自类型的典型特征.Ph染色体和bcr-abl融合基因检测均为阴性.120例MPN患者中JAK2 V617F基因突变的阳性率为66.7％(80/120),其中真性红细胞增多症(PV)为72.7％(16/22),原发性血小板增多症(ET)为66.0％(62/94),4例原发性骨髓纤维化(PMF)患者中2例阳性.JAK2 V617F突变阳性PV患者的外周血白细胞计数(P=0.001)和血小板计数(P=0.010)均高于阴性患者;JAK2 V617F突变阳性ET患者的白细胞计数高于阴性患者(P=0.006);PMF中JAK2V617F突变阳性和阴性患者间各项指标差异均无统计学意义(均P＞0.05).结论 JAK2 V617F基因突变检测有助于bcr-abl阴性MPN的诊断和鉴别诊断,使患者能够在早期被发现和治疗.     

A sensitive and reliable semi-quantitative real-time PCR assay to detect JAK2 V617F in blood

Diagnosis of the myeloproliferative disorders, polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF) is difficult due to lack of diagnostic markers. Recently, the acquisition of a mutation in the Janus kinase 2 (JAK2) gene by hemopoietic cells has been described as a genetic defect underlying myeloproliferative disorders. The mutation leads to constitutive activation of JAK2, a tyrosine kinase involved in cytokine receptor signalling. Because of the clinical importance of this mutation (JAK2 V617F) in diagnosing myeloproliferative disorders and its relevance for disease progression, we developed a semi-quantitative real-time PCR test to detect JAK2 V617F. With this assay, quantities down to 0.8% JAK2 V617F amongst wild-type DNA could reliably be detected. For quantification purposes, low intra- and inter-assay variabilities ensure good reproducibility of the assay. Thus the JAK2 V617F qPCR assay described here is quick, robust, simple and more sensitive than direct sequencing, RFLP, ARMS assay and other methods published so far to detect JAK2 V617F. We therefore believe that the assay will contribute to early diagnosis of myeloproliferative disorders and to disease management, especially when JAK2-specific inhibitors have become available for therapeutic use.     

JAK2 V617F, MPL W515L and JAK2 exon 12 mutations in Chinese patients with primary myelofibrosis

Objective: JAK2 V617F, MPL W515L and JAK2 exon 12 mutations are novel acquired mutations that induce constitutive cytokine-independent activation of the JAK-STAT pathway in myeloproliferative disorders (MPD). The discovery of these mutations provides novel mechanism for activation of signal transduction in hematopoietic malignancies. This research was to investigate their prevalence in Chinese patients with primary myelofibrosis (PMF). Methods: We introduced allele-specific PCR (AS-PCR) combined with sequence analysis to simultaneously screen JAK2 V617F, MPL W515L and JAK2 exon 12 mutations in 30 patients with PMF. Results: Fifteen PMF patients (50.0%) carried JAK2 V617F mutation, and only two JAK2 V617F-negative patients (6.7%) harbored MPL W515L mutation. None had JAK2 exon 12 mutations. Furthermore, these three mutations were not detected in 50 healthy controls.Conclusion: MPL W515L and JAK2 V617F mutations existed in PMF patients but JAK2 exon 12 mutations not. JAK2 V617F and MPL W515L and mutations might contribute to the primary molecular pathogenesis in patients with PMF.     

Burkitt leukemia with precursor B-cell features that developed after ruxolitinib treatment in a patient with hydroxyurea-refractory JAK2V617F-myeloproliferative neoplasm

A 62-year-old woman, who had a 16-year history of JAK2^V617F-mutated myeloproliferative neoplasm (MPN), developed Burkitt leukemia (BL) 16 months after treatment with ruxolitinib to control hydroxyurea-refractory conditions. BL cells were CD10⁺, CD19⁺, CD20⁻, CD34⁻, cytoplasmic CD79a⁺, and TdT⁺, and lacked surface immunoglobulins but expressed the cytoplasmic μ heavy chain. In the bone marrow, nuclear MYC⁺ BL cells displaced the MPN tissues. t(8;14)(q24;q32) occurred at a CG dinucleotide within MYC exon 1 and at the IGHJ3 segment, and an N-like segment was inserted at the junction. The V-D-J sequence of the non-translocated IGH allele had the unmutated configuration. DNA from peripheral blood at a time of the course of MPN exhibited homozygous JAK2^V617F mutation, while that at BL development included both JAK2^V617F and wild-type DNAs. Although the association between JAK1/2 inhibitor therapy for MPN and secondary development of aggressive B-cell neoplasm remains controversial, this report suggests that, in selected patients, close monitoring of clonal B-cells in the BM is required before and during treatment with JAK1/2 inhibitors.