Differential expression of JAK2 and Src kinase genes in response to hydroxyurea treatment in polycythemia vera and essential thrombocythemia.

This study investigates the differential gene expression profile of JAK2(V617F)-positive myeloproliferative neoplasm (MPN) patients, with and without response to hydroxyurea (HU) treatment. Twenty-one polycythemia vera, 28 essential thrombocythemia, eight secondary erythrocytosis, and 30 controls were studied. Thirty-four genes were overexpressed in patients who did not respond to HU. Of these, some participate in proliferative pathways: MAPK, AKT, Src kinase (SFK), and JAK2 pathway. JAK2 allele burden was similar between groups of responders and nonresponder. A molecular fingerprint distinguishes JAK2(V617F)-positive MPN patients without response to HU treatment, with overexpression of JAK2, MAPK14, PIK3CA, and SFK genes.