NPM1 and acute myeloid leukemia: Increased GAB2 expression, however, is substantially more common in AML (35% of AML patient samples from The Cancer Genome Atlas [TCGA] AML study have GAB2 mRNA expression >1.5-fold higher than that of CD34+ cells) and is associated with NPM1 mutations, RTK/RAS signaling mutations, and PML::RARA fusions.