DUSP6 and cancer: The findings presented here, as well as recent results from others (Shojaee et al., 2015; Leung et al., 2018; Wittig-Blaich et al., 2017), support several underlying features of a therapeutic strategy based on inordinate signaling activity involving RAS proteins: that the activity of ERK needs to be actively controlled in cancer cells of diverse tissue origins; that hyperactivation of ERK can be deleterious to cells; and that inhibition of negative regulators like DUSP6 can create a toxic cellular state.