MYELOPROLIFERATIVE DISEASE AND MYELODYSPLASTIC SYNDROME INDUCED BY TRANSPLANTATION OF BONE-MARROW CELLS EXPRESSING MUTANT P53

p53 mutations are the most common genetic alterations observed in huma n cancers including lymphomas and leukemias. We have previously shown that transduction of normal murine hematopoietic cells with mutant p53 alone in vitro results in an enhanced proliferative capacity and modi fied differentiation potential of transduced cells. In order to invest igate further the role of mutant p53 in hematopoietic cell transformat ion, mutant p53-transduced bone marrow cells were used to reconstitute the hematopoietic system of lethally irradiated mice. The results sho w that overexpression of mutant p53 can initiate the transformation of immature murine hematopoietic cells in vivo and induce two types of h ematopoietic disorders, myeloproliferative disease and myelodysplastic syndrome.