【Objective】 To explore the therapeutic effect of interferon alpha (IFN-α) in patients with myeloproliferative neoplasm (MPN) as well as its effect on JAK2V617F gene expression. 【Methods】 In the present study

clinical data and JAK2V617F gene expression were evaluated in 73 cases of MPN patients who had been treated with IFN-α for more than 6 months

in comparison to the control group which consisted of 20 cases of MPN patients treated with hydroxyurea. The expression of JAK2V617F was evaluated before and after the treatment by AS-PCR method.【Results】After 6 months of IFN-α treatment

85.2% of MPN patients with polycythemia vera and 87% of MPN patients with essential thrombocythemia achieved complete remission or partial remission. The difference is statistically significant in comparison to the results of the control group with hydroxyurea treatment(P < 0.01). In MPN patients presented with positive JAK2V617F gene expression

continuous treatment with IFN-α1 for 1 to 6 years reversed the gene expression to negative in 54% (13/24) of the cases with polycythemia vera and 41% (13/32) of the cases with essential thrombocythemia. All of these cases with reversed gene expression remained complete remission. No reversion of JAK2V617F gene expression could be observed in the control group with hydroxyurea treatment. Although the major side effect of IFN-α was flu-like syndrome

all of the patients in this study could tolerate the therapy well. 【Conclusion】 In the present study

IFN-α has shown promising therapeutic response and patient tolerance in the management of MPN. JAK2V617F might be used as one of the important markers to evaluate whether MPN patients have been achieved molecular biologic remission.