RASSF1 is a protein similar to the RAS effector proteins.  RASSF1 plays a crucial role in cellular signaling pathways, particularly in the regulation of cell death and tumor suppression. Located at the human lung tumor suppressor locus 3p21.3, RASSF1 gene produces two major alternative transcripts, RASSF1A and RASSF1C, which interact with activated Ras proteins in a GTP-dependent manner. This interaction suggests RASSF1 may act as a Ras effector, mediating the apoptotic effects of oncogenic Ras, thereby influencing cell fate decisions such as senescence and apoptosis. Notably, RASSF1A is often epigenetically inactivated in various cancers, including lung and breast cancers, through hypermethylation of its promoter region, leading to a loss of its tumor suppressor function.