ERBB2 and neoplasm: In tumor cells, persistent activation of ErbB2 and EGFR triggers similar intracellular signaling proteins and pathways as their wild‐type counterparts, including the mitogen‐activated protein kinase (MAPK), PI3K/Akt, and mammalian target of rapamycin (mTOR) pathways, Src kinase, and signal transducer and activator of transcription (STAT) factors.