MAPK3 and myeloproliferative disorder: In addition, Anand et al [9] described higher values of constitutive p-ERK1/2 in CD34+ cells from BM of MF patients, while Teofili et al, using an immune-histochemical approach, did not find any difference in both constitutive p-STAT5 and p-STAT3 in BM CD34+ cells of patients with MF compared to subjects without a myeloproliferative disease [8].