Brief Communication abstract
Nature Cell Biology 3, 198 - 203 (2001)
Published online: 18 January 2001 | doi:10.1038/35055110
Escape from premature senescence is not sufficient for oncogenic transformation by Ras
Daniel S. Peeper1,2, Jan-Hermen Dannenberg1,2, Sirith Douma1, Hein te Riele1 & René Bernards1
Resistance of primary cells to transformation by oncogenic Ras has been attributed to the induction of replicative growth arrest1, 2, 3. This irreversible 'fail-safe mechanism' resembles senescence and requires induction by Ras of p19ARF and p53 (refs 3–5). Mutation of either p19ARF or p53 alleviates Ras-induced senescence and facilitates oncogenic transformation by Ras3, 6, 7. Here we report that, whereas Rb and p107 are each dispensable for Ras-induced replicative arrest, simultaneous ablation of both genes disrupts Ras-induced senescence and results in unrestrained proliferation. This occurs despite activation by Ras of the p19ARF /p53 pathway, identifying pRb and p107 as essential mediators of Ras-induced antiproliferative p19ARF/p53 signalling. Unexpectedly, in contrast to p19ARF or p53 deficiency, loss of Rb/p107 function does not result in oncogenic transformation by Ras, as Ras-expressing Rb-/-/p107-/- fibroblasts fail to grow anchorage-independently in vitro and are not tumorigenic in vivo. These results demonstrate that in the absence of both Rb and p107 cells are resistant to p19ARF/p53-dependent protection against Ras-induced proliferation, and uncouple escape from Ras-induced premature senescence from oncogenic transformation.
- Division of Molecular Carcinogenesis and Center for Biomedical Genetics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
- These authors contributed equally to this work
Correspondence to: René Bernards1 e-mail: bernards@nki.nl
