[Clinical Value of Genetic Susceptibility Genes for Myeloid Neoplasm in Myeloproliferative Neoplasm]

OBJECTIVE

To investigate the influence of genetic susceptibility genes for myeloid tumors on the clinical characteristics of patients with myeloproliferative neoplasm (MPN).

METHODS

Two hundred and thirty-two patients with MPN diagnosed at the Second Hospital of Tianjin Medical University from September 2017 to December 2021 were collected, myeloid neoplasm-related genes were detected by targeted next-generation sequencing, and germline mutations were verified. The clinical characteristics and prognosis of MPN patients with germlines mutations in the genetic susceptibility gene for myeloid neoplasm were analyzed.

RESULTS

The germline mutation carrier rate of myeloid neoplasm genetic susceptibility gene in MPN patients was 21.6% (50/232), and the PV, ET and PMF patients carrying germline mutations of genetic susceptibility gene for myeloid neoplasm were 25/114 (21.9%), 8/69 (11.6%) and 17/49 (34.7%), respectively, among which PMF patients had the highest carrier rate (P=0.01) and were older (P=0.02). The incidence of chromosomal abnormalities in MPN patients carrying the genetic susceptibitity genes for myeloid neoplasm was higher than that in the non-carrier group (26.5% vs 11.8%, P=0.05). Germline mutations in the genetic susceptibility gene of myeloid neoplasm in MPN patients were mainly concentrated in the RAS pathway, and patients with germline mutations in the genetic susceptibility gene of myeloid neoplasm associated with the RAS pathway had shorter survival without AML progression (P<0.0001). The overall survival time in MPN patients with CBL and TP53 germline mutations was shorter than that of non-carrier group (P=0.001; P=0.043).

CONCLUSION

In MPN, PMF patients are more likely to carry germline mutations in the genetic susceptibility gene for myeloid neoplasm. MPN patients with germline mutations carring the genetic susceptibility gene for myeloid neoplasm are prone to chromosomal abnormalities; Patients with MPN who have germline mutations in the genetic susceptibility gene for myeloid neoplasm in the RAS pathway are more likely to develop AML; CBL and TP53 germline mutations affect the overall survival of MPN patients.

[Visceral Vein Thrombosis of Myeloproliferative Neoplasm --Review]

Classical myeloproliferative neoplasm (MPN) related thrombosis mainly affects elderly patients and often involves arterial circulation, while, MPN-visceral venous thrombosis (SVT) mainly affects young women, and is closely associated with JAK2V617F mutation but not closely with CALR mutation. The pathogenesis of MPN-SVT is not only related to JAK2V617F mutation and vascular endothelial damage, but also needs further research to determine the machanism. JAK2V617F mutation is the most common in MPN-SVT clinically. Patients with non-cirrhotic SVT need to detect MPN mutation, while the detection of CALR or MPL mutation needs to be combined with clinical judgment. At present, the main treatment strategies of MPN-SVT are JAK inhibitors, supplementation of anticoagulants and treatment of portal hypertension. This article reviews the latest research progress on the epidemiology, pathogenesis, diagnosis and treatment strategies of MPN-SVT.

[Clinical Analysis of Gene Mutation and Vascular Events in Patients with BCR/ABL Negative Myeloproliferative Neoplasms]

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.

[Analysis of DNA Methylation Gene Mutations and Clinical Features in Patients with Myeloproliferative Neoplasm]

AbstractObjective: To analyze the DNA methylation gene mutations of myeloproliferative neoplasm (MPN), and preliminarily explore its clinical features.

METHODS

Next-generation sequencing technology was used to detect 31 MPN-related genes in 105 cases of MPN patients ［40 cases of polycythaemia vera (PV), 65 cases of essential thrombocythemia (ET)］, and to analyze the relationship between DNA methylation gene mutations and clinical features.

RESULTS

15 mutation types were detected in 105 patients (88 mutations in total), and the total mutation detection rate was 87.6% (92/105). A total of 23 mutations in 4 DNA methylation genes (TET2, DNMT3A, IDH1, IDH2) were detected in 22 patients. The mutation rate of DNA methylation genes was 21.0%, mainly in the form of double mutations, including JAK2 V617F and TET2 (n=10), JAK2 V617F and DNMT3A (n=4), CALR and TET2 (n=2), JAK2 V617F and IDH1 (n=1). Compared with MPN patients without DNA methylation gene mutations, the proportion of women with DNA methylation gene mutations and the white blood cell count (WBC) were significantly higher (P<0.05). Compared with MPN patients with triple-negative driver genes, the proportion of women with DNA methylation gene mutations, age, WBC, platelet count (PLT), and neutrophil-to-lymphocyte ratio (NLR) were significantly higher (P<0.05). The remaining difference was not statistically significant (P>0.05). The MPN10 score, the incidence of thrombotic events, and the proportion of medium-risk and high-risk patients with DNA methylation gene mutations were significantly higher than those of MPN patients without DNA methylation gene mutations (P<0.05).

CONCLUSION

The mutation rate of DNA methylation genes was 21.0%, mainly coexisting in the form of double mutations. The proportion of women with DNA methylation gene mutations in MPN patients and WBC is high, the symptom load is heavy, the incidence of thrombosis is high, and the proportion of medium-high-risk patients is high, suggesting that their prognosis may be poor.