For example, some deregulation Arf isoforms from the small GTPase subfamily induce cancer formation and progression by enhancing cell proliferation through the activation of mitogen-activated protein kinases (MAPK) and ribosomal protein S6 kinase beta-1 (p70S6K) (Davis et al., 2016; Li et al., 2017). The gene discussed is CDKN2A; the disease is cancer.