Larsen Thomas Stauffer, Pallisgaard Niels, Møller Michael Boe, Hasselbalch Hans Carl
Department of Haematology, Odense University Hospital, Denmark.
Hematology. 2008 Apr;13(2):71-6. doi: 10.1179/102453308X315960.
Approximately half of the patients with essential thrombocythaemia (ET) harbor the JAK2 V617F mutation. Despite a phenotypic mimicry of JAK2 V617F positive ET and polycythaemia vera (PV), the data on thromboembolic risk and correlation to JAK2 mutation status are ambiguous. On a strictly WHO defined ET cohort we evaluated possible clinical correlations to the JAK2 mutation status including a history of previous thrombosis. We used a highly sensitive quantitative real-time PCR (qPCR) assay for JAK2 V617F detection and allele burden quantification in a single institution study of 55 patients. A significantly increased prevalence of arterial thrombosis was recorded in JAK2 positive ET (p=0.001). There was no association between the mutational load and thrombosis. As compared to their JAK2 V617F negative counterparts, the JAK2 V617F positive patients had PV-like biochemical characteristics such as higher haemoglobin levels (p=0.02), lower platelet counts (p=0.002) and lower plasma EPO levels (p=0.04). The JAK2 V617F mutation per se but not the mutational load in patients with ET is associated with a PV-like phenotype and a higher prevalence of previous arterial thrombosis. This study adds further support to the contention of the JAK2 V617F mutation as a marker of increased risk of thrombosis.
大约一半的原发性血小板增多症（ET）患者携带JAK2 V617F突变。尽管JAK2 V617F阳性ET与真性红细胞增多症（PV）在表型上存在相似之处，但关于血栓栓塞风险以及与JAK2突变状态的相关性数据并不明确。在一个严格按照世界卫生组织定义的ET队列中，我们评估了与JAK2突变状态可能存在的临床相关性，包括既往血栓形成史。在一项对55例患者的单机构研究中，我们使用了一种高灵敏度的定量实时聚合酶链反应（qPCR）检测方法来检测JAK2 V617F并定量等位基因负荷。JAK2阳性ET患者的动脉血栓形成患病率显著增加（p = 0.001）。突变负荷与血栓形成之间没有关联。与JAK2 V617F阴性患者相比，JAK2 V617F阳性患者具有类似PV的生化特征，如更高的血红蛋白水平（p = 0.02）、更低的血小板计数（p = 0.002）和更低的血浆促红细胞生成素（EPO）水平（p = 0.04）。ET患者中JAK2 V617F突变本身而非突变负荷与类似PV的表型以及既往动脉血栓形成的较高患病率相关。这项研究进一步支持了JAK2 V617F突变作为血栓形成风险增加标志物的观点。
