Blast crisis is the terminal phase of chronic myelogeneous leukemia (CML), a clonal myeloproliferative disorder of the hematopoietic stem cell that typically involves in three distinct clinical stages: chronic, accelerated phase and blast crisis. The chronic phase lasts several years and is characterized by accumulation of myeloid precursors and mature cells in bone marrow. The blast crisis lasts only a few months and is characterized by rapid expansion of a population of myeloid or lymphoid differentiation-arrested blast cells which are associated with the Philadelphia chromosome (Ph), a shortened chromosome 22 resulting from a reciprocal translocation of the long arms of chromosomes 9 and 22. This translocation generates the BCR-ABL fusion gene that produces a p210 oncoprotein, in almost all patients with CML. The mechanisms responsible for transition of CML chronic phase into blast crisis remain poorly understood, although a reasonable assumption is that the unrestrained activity of BCR/ABL in hematopoietic stem progenitor cells is the primary determinant of disease progression. Thus, in this work, to better understand this event we analyzed using proteomic tools, like 2D gels and mass spectrometry, the protein modifications that occurs in the blastic evolution of bone marrow cells from chronic  myeloid leukemia patients. To reach this goal protein extracts, were analyzed through a high-resolution two-dimensional (2D) electrophoresis assay in the Multiphor II electrophoresis System (GE). Seven hundred micrograms of 10 patients in chronic phase and 10 patients in blastic phase was precipitated and used in the 2-D gels. The proteins were separated using a 11cm ImmobilineDrystrip (GE) of pH 4-7, for 78kVh. The second dimension was done in a 8-18% gradient SDS-PAGE gel in a Multiphor II (GE) apparatus. The gels were analyzed and all protein-spots were identified by Mass spectrometry in a MALDI-TOF-TOF instrument (4700 Applied Biosystems). Using this approach we identified 250 proteins present in each sample and 42 differentially expressed protein spots between the samples. Taken together the results shown a global blastic protein expression reduction excepted by protein like Ras, NuMA1 isoforms  and proteins from Wint signaling pathway like Disheveled and Beta-catenin that could represents blastic phase functional biomarkers.