AKT1 and neoplasm: Indeed, none of these mutant alleles induced expression of p-AKT, including the E267G and R370C mutations that were previously shown to cause tumor formation when expressed in HA1E-M cells18—a difference with prior work that may reflect a lineage-specific difference in their ability to stimulate pathway activity or perhaps was attributable to HA1E-M cells expressing constitutively active MEK1DD.