“…p53-inactivating mutations were identified in o15% of chronic phase hematological malignancies, including chronic myelogenous leukemia (Kantarjian et al, 1987;Feinstein et al, 1991;Hernandez-Boussard et al, 1999), PV (Gaidano et al, 1997) and PMF (Tsurumi et al, 2002;Reilly, 2005) and more than half of MPN in blast crisis (Gaidano et al, 1997;Tsurumi et al, 2002). In the absence of mutation, p53 function can be inactivated by an increased expression of MDM2, an E3 ubiquitin ligase that binds to p53 and promotes its proteosomal degradation (Freedman et al, 1999).…”