PTPN11 mutations, which block autoregulation of SHP2 catalytic activity and lead to hyperactivation of RAS/MAPK, JAK/STAT, PI3K/AKT signaling, are responsible for the development of the prosurvival and resistant phenotype in myeloid leukemias and are associated with an overall poor prognosis. This evidence concerns the gene PTPN11 and myeloid leukemia.