PBX1 and acute lymphoblastic leukemia: Chromosomal translocations are still the main marker of genetic instability in ALL leukemogenesis, the gene fusions t(1; 19)(q23; p13) that generates E2A-PBX1 and t(9; 22)(q34; q11) that originates the chimeric gene BCR-ABL, were the two more frequent found in ALL cohort analyzed in this study, 20.27% and 12.83%, respectively.