骨髓增殖性肿瘤(myeloproliferative neoplasms,MPN)导致血细胞增加、血液高凝,是非肝硬化门静脉海绵样变性的重要病因。JAK2V617F基因突变可以帮助诊断MPN。我们报道1例JAK2V617F基因突变阳性的MPN患者发生门静脉海绵样变性(cavernous ...骨髓增殖性肿瘤(myeloproliferative neoplasms,MPN)导致血细胞增加、血液高凝,是非肝硬化门静脉海绵样变性的重要病因。JAK2V617F基因突变可以帮助诊断MPN。我们报道1例JAK2V617F基因突变阳性的MPN患者发生门静脉海绵样变性(cavernous transformation of the portal vein,CTPV)。该例患者脾脏显著肿大,一方面是由于骨髓增殖性疾病本身的原因,另一方面是由于PVCT、门脉高压和脾脏淤血造成,表现为外周血血细胞计数基本在正常范围,亦是血细胞增殖和脾脏对血细胞的处理增加的共同作用的结果。抗凝治疗效果差,而应以预防食管曲张静脉破裂出血(EVB)为主。展开更多
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 d...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.展开更多
Patients with IBD frequently have hematologic abnormalities suggestive of JAK2 mutated MPNs, but are traditionally classified as reactive processes. Haplotype 46/1 is a well-characterized genetic predisposition, commo...Patients with IBD frequently have hematologic abnormalities suggestive of JAK2 mutated MPNs, but are traditionally classified as reactive processes. Haplotype 46/1 is a well-characterized genetic predisposition, common to both inflammatory bowel disease (IBD) and myeloproliferative neoplasms (MPN). In view of this shared genetic predisposition, we measured the frequency of the JAK2V617F mutation in IBD patients with thrombocytosis or erythrocytosis, in order to ascertain whether a higher than expected proportion of these patients may in fact have underlying MPNs. 1121 patients were identified with an active diagnosis of Crohn’s disease or ulcerative colitis, of which 474 had either thrombocytosis or erythrocytosis. Patients with abnormal counts were tested for the JAK2V617F mutation during routine follow-up visits. Interim analysis of first 23 patients tested was performed to assess whether the JAK2V617F positivity rate was statistically significant compared with known expected frequencies in a comparable control population. Of 23 patients, 13 patients had thrombocytosis and 10 had erythrocytosis. Three patients with thrombocytosis (23%), and 1 patient with erythrocytosis (10%), tested positive for JAK2V617F, exceeding the expected thresholds for statistical significance. In patients with IBD and thrombocytosis or erythrocytosis, a meaningful proportion may harbor an undiagnosed MPN, as indicated by clonal abnormalities such as JAK2V617F. These findings imply the need for increased testing of these patients for clonal hematologic abnormalities, and importantly, if found, suggest the need for therapeutic strategies with drugs, such as JAK2 inhibitors, in patients with both MPN and IBD.展开更多
BACKGROUND The Janus kinase 2(JAK2) V617 F mutation is common in patients with breakpoint cluster region-Abelson1(BCR-ABL1)-negative myeloproliferative neoplasms,including polycythemia vera, essential thrombocythemia ...BACKGROUND The Janus kinase 2(JAK2) V617 F mutation is common in patients with breakpoint cluster region-Abelson1(BCR-ABL1)-negative myeloproliferative neoplasms,including polycythemia vera, essential thrombocythemia and primary myelofibrosis, but is rarely detected in BCR-ABL1-positive chronic myeloid leukemia(CML) patients. Here, we report a CML patient with both a BCR-ABL1 rearrangement and JAK2 V617 F mutation.CASE SUMMARY A 45-year-old Chinese woman was admitted to our department with a history of significant thrombocytosis for 20 d. Color Doppler ultrasound examination showed mild splenomegaly. Bone marrow aspiration revealed a karyotype of 46,XX, t(9;22)(q34;q11.2) in 20/20 metaphases by cytogenetic analysis,rearrangement of BCR-ABL1(32.31%) by fluorescent polymerase chain reaction(PCR) and mutation of JAK2 V617 F(10%) by PCR and Sanger DNA sequencing.The patient was diagnosed with CML and JAK2 V617 F mutation. Following treatment with imatinib for 3 mo, the patient had an optimal response and BCRABL1(IS) was 0.143%, while the mutation rate of JAK2 V617 F rose to 15%.CONCLUSION Emphasis should be placed on the detection of JAK2 mutation when CML is diagnosed to distinguish JAK2 mutation-positive CML and formulate treatment strategies.展开更多
文摘骨髓增殖性肿瘤(myeloproliferative neoplasms,MPN)导致血细胞增加、血液高凝,是非肝硬化门静脉海绵样变性的重要病因。JAK2V617F基因突变可以帮助诊断MPN。我们报道1例JAK2V617F基因突变阳性的MPN患者发生门静脉海绵样变性(cavernous transformation of the portal vein,CTPV)。该例患者脾脏显著肿大,一方面是由于骨髓增殖性疾病本身的原因,另一方面是由于PVCT、门脉高压和脾脏淤血造成,表现为外周血血细胞计数基本在正常范围,亦是血细胞增殖和脾脏对血细胞的处理增加的共同作用的结果。抗凝治疗效果差,而应以预防食管曲张静脉破裂出血(EVB)为主。
文摘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.
文摘Patients with IBD frequently have hematologic abnormalities suggestive of JAK2 mutated MPNs, but are traditionally classified as reactive processes. Haplotype 46/1 is a well-characterized genetic predisposition, common to both inflammatory bowel disease (IBD) and myeloproliferative neoplasms (MPN). In view of this shared genetic predisposition, we measured the frequency of the JAK2V617F mutation in IBD patients with thrombocytosis or erythrocytosis, in order to ascertain whether a higher than expected proportion of these patients may in fact have underlying MPNs. 1121 patients were identified with an active diagnosis of Crohn’s disease or ulcerative colitis, of which 474 had either thrombocytosis or erythrocytosis. Patients with abnormal counts were tested for the JAK2V617F mutation during routine follow-up visits. Interim analysis of first 23 patients tested was performed to assess whether the JAK2V617F positivity rate was statistically significant compared with known expected frequencies in a comparable control population. Of 23 patients, 13 patients had thrombocytosis and 10 had erythrocytosis. Three patients with thrombocytosis (23%), and 1 patient with erythrocytosis (10%), tested positive for JAK2V617F, exceeding the expected thresholds for statistical significance. In patients with IBD and thrombocytosis or erythrocytosis, a meaningful proportion may harbor an undiagnosed MPN, as indicated by clonal abnormalities such as JAK2V617F. These findings imply the need for increased testing of these patients for clonal hematologic abnormalities, and importantly, if found, suggest the need for therapeutic strategies with drugs, such as JAK2 inhibitors, in patients with both MPN and IBD.
文摘BACKGROUND The Janus kinase 2(JAK2) V617 F mutation is common in patients with breakpoint cluster region-Abelson1(BCR-ABL1)-negative myeloproliferative neoplasms,including polycythemia vera, essential thrombocythemia and primary myelofibrosis, but is rarely detected in BCR-ABL1-positive chronic myeloid leukemia(CML) patients. Here, we report a CML patient with both a BCR-ABL1 rearrangement and JAK2 V617 F mutation.CASE SUMMARY A 45-year-old Chinese woman was admitted to our department with a history of significant thrombocytosis for 20 d. Color Doppler ultrasound examination showed mild splenomegaly. Bone marrow aspiration revealed a karyotype of 46,XX, t(9;22)(q34;q11.2) in 20/20 metaphases by cytogenetic analysis,rearrangement of BCR-ABL1(32.31%) by fluorescent polymerase chain reaction(PCR) and mutation of JAK2 V617 F(10%) by PCR and Sanger DNA sequencing.The patient was diagnosed with CML and JAK2 V617 F mutation. Following treatment with imatinib for 3 mo, the patient had an optimal response and BCRABL1(IS) was 0.143%, while the mutation rate of JAK2 V617 F rose to 15%.CONCLUSION Emphasis should be placed on the detection of JAK2 mutation when CML is diagnosed to distinguish JAK2 mutation-positive CML and formulate treatment strategies.
