CD34 and myeloproliferative disorder: PI3K/AKT/mTOR inhibitors induced cell-cycle growth arrest, apoptosis and blocked colony development from MPN hematopoietic progenitors, whereas co-treatment with JAK2-inhibitors synergistically induced apoptosis of the primary CD34+ MPN cells and significantly reduced erythropoietin-independent colony growth in patients with PV [7,8].