MAPK3 and endometrial cancer: These findings encouraged us to examine the Ras–MAPK–ERK1/2 and PI3K–Akt signaling pathways in endometrial cancer cells, especially since DUSP6 is an ERK1/2‐specific phosphatase, and both signaling pathways are activated by Ras (Fig. 4e).32, 33 To assess activation of these signaling pathways, we measured phosphorylated ERK1/2 and Akt levels by performing Western blot analysis.