title: RASSF6 is a novel member of the RASSF family of tumor suppressors.
abstract: RASSF family proteins are tumor suppressors that are frequently downregulated during the development of human cancer. The best-characterized member of the family is RASSF1A, which is downregulated by promoter methylation in 40-90% of primary human tumors. We now identify and characterize a novel member of the RASSF family, RASSF6. Like the other family members, RASSF6 possesses a Ras Association domain and binds activated Ras. Exogenous expression of RASSF6 promoted apoptosis, synergized with activated K-Ras to induce cell death and inhibited the survival of specific tumor cell lines. Suppression of RASSF6 enhanced the tumorigenic phenotype of a human lung tumor cell line. Furthermore, RASSF6 is often downregulated in primary human tumors. RASSF6 shares some similar overall properties as other RASSF proteins. However, there are significant differences in biological activity between RASSF6 and other family members including a discrete tissue expression profile, cell killing specificity and impact on signaling pathways. Moreover, RASSF6 may play a role in dictating the degree of inflammatory response to the respiratory syncytial virus. Thus, RASSF6 is a novel RASSF family member that demonstrates the properties of a Ras effector and tumor suppressor but exhibits biological properties that are unique and distinct from those of other family members.
authors.affiliation: Department of Cell and Cancer Biology, National Cancer Institute, Rockville, MD, USA.
authors.forename: N P C
authors.initials: NP
authors.lastname: Allen
authors.forename: H
authors.initials: H
authors.lastname: Donninger
authors.forename: M D
authors.initials: MD
authors.lastname: Vos
authors.forename: K
authors.initials: K
authors.lastname: Eckfeld
authors.forename: L
authors.initials: L
authors.lastname: Hesson
authors.forename: L
authors.initials: L
authors.lastname: Gordon
authors.forename: M J
authors.initials: MJ
authors.lastname: Birrer
authors.forename: F
authors.initials: F
authors.lastname: Latif
authors.forename: G J
authors.initials: GJ
authors.lastname: Clark
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D002460:Cell Line; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006131:Growth Inhibitors / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D020559:Monomeric GTP-Binding Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D005810:Multigene Family; D009928:Organ Specificity / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D018631:ras Proteins / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D006131:Growth Inhibitors; C519911:RASSF6 protein, human; D025521:Tumor Suppressor Proteins; D020559:Monomeric GTP-Binding Proteins; D018631:ras Proteins