MAPK3 and neoplasm: In NSCLC, upon M3-mediated EGFR transactivation, the signaling pathway was activated, thus phosphorylating ERK1/2 and AKT [32,94,95], and, under a muscarinic antagonist (R2-8018), the PI3K/AKT and MEK/ERK1/2 pathways were inhibited, therefore, inhibiting tumor growth [82].