MAPK3 and endometrial endometrioid adenocarcinoma: As withOS, activation of the ERK1/2 pathways was a positive biomarker for severalsubtypes of breast cancer and for endometrioid carcinoma of the uterine corpus.In addition (unlike in OS), it was a positive biomarker for the head and neck,liver, and prostate cancers(Fig. 2B).