[Efficacy and safety of pegylated interferon alpha-2b for patients with myeloproliferative neoplasm].

Objective: To evaluate the efficacy and safety of pegylated interferon alpha-2b (PEG-IFN-α2b) in the treatment of myeloproliferative neoplasm (MPN). Methods: Thirty-four MPN patients receiving PEG-IFN-α2b treatment in the Second Hospital of Tianjin Medical University from August 2019 to October 2022 were prospectively included. Among the patients, 9 were male and 25 were female, and the median age [M (Q1, Q3)] was 57 (19, 78) years. Patients' clinical characteristics were collected and the follow-up was performed. As of January 30, 2023, the follow-up period [M(Q1, Q3)] was 24 (16, 33) months. The efficacy, safety and changes in immune cell and cytokine levels after 12 and 24 months of treatment were analyzed. Results: During the follow-up period, 4 patients dropped out, and the efficacy was evaluable in 30 patients. Following 12 and 24 months of treatment, the complete hematologic response (CHR) rates were 57.1% (16/28) and 75.0% (18/24), respectively. The complete molecular response (CMR)+partial molecular response (PMR) rates were 27.3% (6/22) and 55.0% (11/20), respectively. The bone marrow histopathological overall response rates (ORR) were 34.6% (9/26) and 47.6% (10/21), respectively. At 12 and 24 months of treatment, the proportions of CD8+HLA-DR+T cells, effector T cell subpopulations, CD56bright natural killer (NK) cells, and plasmacytoid dendritic cells (pDC) were higher than the pre-treatment levels, while the proportion of CD56dim NK cells was lower than the pre-treatment level (all P<0.05). The levels of motif chemokine ligand 10 (CXCL10), tumor necrosis factor (TNF)-α and TNF-ß in bone marrow all increased from those prior to treatment, while the levels of vascular endothelial growth factor (VEGF) and interleukin (IL-4) decreased from those prior to treatment (all P<0.05). Among hematological adverse reactions, white blood cells decrease [47% (16/34)] was observed with high incidence. Among non-hematological adverse reactions, asthenia [44.1% (15/34)] and transaminases increase [32.3% (11/34)] were observed with high incidences. Conclusions: PEG-IFN-α2b has high hematologic, molecular, and bone marrow histopathological response rates in the treatment of MPN. It can reduce malignant clone loads and regulate the immune microenvironment and is safe and well tolerated overall.

[Analysis of risk factors for thromboembolism in patients with JAK2V617F gene mutation positive myeloproliferative neoplasms].

Objective: To analyze the risk factors of thrombosis in patients with JAK2V617F mutation positive myeloproliferative neoplasms (MPN). Methods: A total of 223 MPN patients with JAK2V617F mutation in the Second Hospital of Tianjin Medical University from September 2017 to May 2023 were retrospectively enrolled, including 111 males and 112 females, aged [M(Q1,Q3)] 57(21,66) years. According to the presence or absence of thromboembolism during follow-up, the patients were divided into thrombosis group (n=102) and non-thrombosis group (n=121). The clinical characteristics, laboratory characteristics, cytogenetics and other disease progression and survival of the two groups of patients were analyzed. As of March 31, 2023, the follow-up period [M (Q1, Q3)] was 6 (3, 10) years. The influencing factors of thrombosis in JAK2V617F positive MPN patients were analyzed by using the Cox risk model. Results: Among 223 JAK2V617F positive MPN patients, 144 were polycythemia vera (PV), 51 were essential thrombocythemia (ET) and 28 were primary myelofibrosis (PMF). The mutation rates of ASXL1 and BCORL1 genes in the thrombosis group were 19.6% (20/102) and 6.9% (7/102), respectively, which were higher than those in the non-thrombosis group [9.1% (11/121) and 0.8% (1/121)] (both P<0.05). The proportion of monocytes, C-reactive protein (CRP), interleukin-1ß (IL)-1ß, IL-8 and tumor necrosis factor-ß (TNF-ß) increased in the thrombosis group were higher than those in the non-thrombosis group (all P<0.05). Multivariate analysis showed that age≥60 years (HR=2.132, 95%CI: 1.376-3.303, P=0.001), history of thrombosis (HR=3.636, 95%CI: 2.121-6.202, P<0.001), ASXL1 mutation positive (HR=2.245, 95%CI: 1.093-3.231, P=0.022) and elevated TNF-ß (HR=2.009, 95%CI: 1.113-3.624, P=0.021) were risk factors for thrombosis in JAK2V617F positive MPN patients. Conclusions: In addition to age, history of thrombosis and positive ASXL1 mutation, elevated TNF-ß is also an influencing factor of thrombosis in JAK2V617F positive MPN patients. Intervention of inflammation may have a certain effect on the prevention and treatment of thrombosis.

[Clinical and laboratory features of SF3B1-mutated myeloproliferative neoplasms].

Objective: To explore the clinical and laboratory characteristics of SF3B1 gene mutations in myeloproliferative neoplasms (MPN) patients. Methods: The clinical data of 273 MPN patients who were diagnosed MPN and treated in the Second Hospital of Tianjin Medical University from November 2017 to March 2023 were retrospectively analyzed. There were 133 males and 140 females, with a median age M(Q1,Q3)of 56(46, 67) years. The molecular biology and cytogenetic characteristics were detected by second-generation sequencing (NGS) and R+G banding techniques, and the clinical and laboratory characteristics of patients with SF3B1 gene mutation were analyzed. Results: SF3B1 gene mutations were found in 13 patients (4.8%, 13/273).The types of SF3B1 mutations included missense (92.3%, 12/13) and nonsense mutations (7.7%, 1/13).Compared to the non-mutant cohort, patients in SF3B1 mutant cohort had older ages [68(51, 76) vs 56(45, 66)years,P=0.025], higher proportion of splenomegaly [46.2%(6/13) vs 15.8%(41/259),P=0.014]and secondary tumor [23.1%(3/13)vs 3.8%(10/260), P=0.018]with higher proportion of bone marrow blast [0.5%(0, 1.5%) vs 0(0, 0.5%),P=0.002] and lower hemoglobin[(104±36) vs (137±40) g/L,P=0.004] and hematocrit [31%(22%, 40%) vs 41%(35%, 52%),P=0.003]. All of the 10 patients in the SF3B1 mutant cohort whose ring sideroblast (RS) could be evaluated showed no RS formation. The overall survival, thrombosis-free survival and leukemia free survival of MPN patients in SF3B1 mutant cohort were 4.0 (2.0, 6.0), 2.0 (0.5, 4.5) and 4.0 (2.0, 6.0) years, respectively, while patients in the non-mutant cohort were 6.0 (3.0, 10.0), 5.0 (1.0, 8.0), 6.0 (3.0, 10.0) years, respectively, there were no statistical significance between two groups (Z=3.69, 1.66, 2.05, all P>0.05).The secondary tumor free survival of SF3B1 mutant cohort patients was 4.0 (2.0, 6.0) years, which was lower than that of non-mutant cohort patients [5.5 (3.0, 10.0) years, Z=18.18, P<0.001). Conclusions: MPN patients with SF3B1 gene mutations are older, more prone to splenomegaly and secondary tumors. They also have a higher proportion of bone marrow blast, lower hemoglobin and hematocrit, and show no RS formation.