RAF1 and cancer: In summary, harmine specifically suppresses the Muv phenotypes caused by let-60(n1046gf) and LIN-45/Raf-AA (S312A/S453A), and suppresses germ-line developmental defects in let-60(ga89), suggesting that harmine only targets some mutationally activated Ras and Raf proteins and may therefore serve as an anti-cancer drug for a specific set of tumors.