MAPK1 and cancer: The Ras–MAPK–ERK signaling pathway transduces signals downstream of growth factor receptors, and is an important mediator of cell proliferation during embryonic development and in cancer (Kamiya et al., 2015; Maekawa et al., 2007; Steinmetz et al., 2004; Wong et al., 2018; Yang et al., 2020; Zhou et al., 2019).