ABSTRACT
Objective To analyze the relationship between the JAK2V617F mutation and the expressions of phosphorylated Janus kinase 2 (p-JAK2), suppressor of cytokine signaling 1 (SOCS1), and SH2-containing protein tyrosine phosphatase 1 (SHP1) in JAK2V617F mutation positive myeloproliferative neoplasm (MPN) tissues, and to investigate the effects of JAK2 inhibitor ruxolitinib on regulating the proliferation of JAK2V617F mutation positive human erythroleukemia cell lines HEL and the expressions of SOCS1 and SHP1 in HEL cells. Methods A total of 48 patients with JAK2V617F mutation positive MPN (MPN group) and 24 patients with anemia (control group) in Hebei General Hospital and The First People’s Hospital of Baoding from Jul. 2012 to Aug. 2016 were enrolled in this study. The protein expressions of p-JAK2, SOCS1 and SHP1 in bone marrow biopsies (BMBs) were detected by immunohistochemistry. The correlations between JAK2V617F mutation level and the protein expressions of SOCS1 and SHP1 were analyzed by Spearman rank correlation analysis. HEL cells were treated with ruxolitinib at different concentrations (50, 100, 250, 500 and 1 000 nmol/L), and the viability of cells was determined by CCK-8 assay. The JAK2V617F mutation levels in MPN tissues and HEL cells and the mRNA expressions of JAK2, SOCS1 and SHP1 in HEL cells were detected by qPCR. The protein expressions of JAK2, SOCS1 and SHP1 in HEL cells were detected by Western blotting analysis. Results The ratio of JAK2V617F/JAK2 was (57.33±20.82)% in the MPN group and was zero in the control group. The protein expressions of p-JAK2, SOCS1 and SHP1 in BMBs of MPN patients were significantly different from those in the control group (all P0.01). The protein expressions of SOCS1 and SHP1 were negatively correlated with the mutation level of JAK2V617F (r＝－0.648, －0.692; P0.05). The expressions of SOCS1 and SHP1 in MPN patients with JAK2V617F/JAK250% were significantly higher than those in MPN patients with JAK2V617F/JAK2≥50% (P0.01), while the expression of p-JAK2 was significantly lower than that in MPN patients with JAK2V617F/JAK2≥50% (P0.01). After treatment with 250 nmol/L ruxolitinib for 24 h, 48 h, and 72 h, the viabilities of HEL cells were (60.06±3.87)%, (52.05±2.88)%, and (36.43±2.01)%, respectively. With the increase of ruxolitinib concentrations, the mRNA and protein expressions of JAK2 and the protein expression of p-JAK2 were gradually decreased (P0.01, P0.05), while the mRNA and protein expressions of SOCS1 and SHP1 were gradually increased (all P0.01). Conclusion Ruxolitinib can inhibit the expressions of JAK and the phosphorylation of JAK in HEL cells, enhance the expressions of SOCS1 and SHP1, and reduce the viability of HEL cells.
ABSTRACT
This study was aimed to investigate the clinical characteristics of acute myeloid leukemia (AML) with t (8;21) (q22;q22) and loss of Y chromosomes. Clinical data of 267 cases of AML were collected from January 2010 to June 2013. Among 267 AML, there were 13 cases with t (8;21) (q22;q22) and loss of Y chromosomes. The clinical data including clinical indicators, treatment protocols, curative effect and prognosis were analyzed retrospectively. The results showed that after normalized chemotherapy, there were 4 patients with complete remission at the first cycle of treatment, 4 patients with complete remission at the second cycle, 4 patients with complete remission at the third cycle, but one patient without complete remission after 4 cycles. There were 6 patients who did not relapse during consolidation and intensive therapy. Among these 6 patients, 4 cases accepted chemotherapy combined with transplantation, other 2 cases accepted chemotherapy. In the remainder 6 patients, 4 cases relapsed once, one cases relapsed twice, 1 cases relapsed for three times. Moreover, 2 cases who accepted the chemotherapy and auto-hematopoietic stem cell trans-plantation, were diagnosed as relapse, after accepted allo-hematopoietic stem cell transplantation, currently are in disease-free status. In follow-up period, the relapse-free survival (RFS) time was 4.67 ± 3.45 months in chemotherapy group, the RFS time is 34.17 ± 21.37 months in chemotherapy and transplantation group. The chemotherapy combined with transplantation extended the RFS time (P < 0.05). It is concluded that the NCCN guide indicates that AML with t (8;21) ( q22;q22) showed a good prognosis. but the clinical course of treatment confirmed that the prognosis of AML patients with t (8;21) (q22;q22) and loss Y chromosomes is poor, including uneasy remission and easy relapse, for improving the prognosis of these patients, the hematopoietic stem cell transplantation should be recommended.