MAPK3 and lung adenocarcinoma: In human KRAS mutant lung adenocarcinoma, downstream effectors of KRAS interacted with Akt/mTOR signaling pathway, receptors of tyrosine kinase and adaptor proteins, and the activation levels of ERK1/2 in two‐thirds of lung adenocarcinomas with KRAS mutation were comparable with that of wild‐type 31.