title: p53-independent functions of the p19(ARF) tumor suppressor.
abstract: The p19(ARF) tumor suppressor antagonizes Mdm2 to induce p53-dependent cell cycle arrest. Individual TKO (triple knock out) mice nullizygous for ARF, p53, and Mdm2 develop multiple tumors at a frequency greater than those observed in animals lacking both p53 and Mdm2 or p53 alone, demonstrating that p19(ARF) can act independently of the Mdm2-p53 axis in tumor surveillance. Reintroduction of ARF into TKO mouse embryo fibroblasts (MEFs), but not into those lacking both p53 and ARF, arrested the cell division cycle in the G1 phase. Inhibition of the retinoblastoma protein had no effect on the ability of ARF to arrest TKO MEFs. Thus, in the absence of Mdm2, p19(ARF) interacts with other targets to inhibit cell proliferation.
authors.affiliation: Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Weber
authors.forename: J R
authors.initials: JR
authors.lastname: Jeffers
authors.forename: J E
authors.initials: JE
authors.lastname: Rehg
authors.forename: D H
authors.initials: DH
authors.lastname: Randle
authors.forename: G
authors.initials: G
authors.lastname: Lozano
authors.forename: M F
authors.initials: MF
authors.lastname: Roussel
authors.forename: C J
authors.initials: CJ
authors.lastname: Sherr
authors.forename: G P
authors.initials: GP
authors.lastname: Zambetti
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D016147:Genes, Tumor Suppressor; D015151:Immunoblotting; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009369:Neoplasms / Q000235:genetics / Q000473:pathology; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology; D051736:Proto-Oncogene Proteins c-mdm2; D025803:Tumor Suppressor Protein p14ARF; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000502:physiology*
chemical_list: D009687:Nuclear Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D025803:Tumor Suppressor Protein p14ARF; D016159:Tumor Suppressor Protein p53; C497207:Mdm2 protein, mouse; D051736:Proto-Oncogene Proteins c-mdm2