title: Dissecting the senescence-like program in tumor cells activated by Ras signaling.
abstract: Activated Ras signaling can induce a permanent growth arrest in osteosarcoma cells. Here, we report that a senescence-like growth inhibition is also achieved in human carcinoma cells upon the transduction of H-Ras(V12). Ras-induced tumor senescence can be recapitulated by the transduction of activated, but not wild-type, MEK. The ability for H-Ras(V12) to suppress tumor cell growth is drastically compromised in cells that harbor endogenous activating ras mutations. Notably, growth inhibition of tumor cells containing ras mutations can be achieved through the introduction of activated MEK. Tumor senescence induced by Ras signaling can occur in the absence of p16 or Rb and is not interrupted by the inactivation of Rb, p107, or p130 via short hairpin RNA or the transduction with HPV16 E7. In contrast, inactivation of p21 via short hairpin RNA disrupts Ras-induced tumor senescence. In summary, this study uncovers a senescence-like program activated by Ras signaling to inhibit cancer cell growth. This program appears to be intact in cancer cells that do not harbor ras mutations. Moreover, cancer cells that carry ras mutations remain susceptible to tumor senescence induced by activated MEK. These novel findings can potentially lead to the development of innovative cancer intervention.
authors.affiliation: Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
authors.forename: Teeru
authors.initials: T
authors.lastname: Bihani
authors.forename: Agustin
authors.initials: A
authors.lastname: Chicas
authors.forename: Crystal Pui-Kwan
authors.initials: CP
authors.lastname: Lo
authors.forename: Athena W
authors.initials: AW
authors.lastname: Lin
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation; D016922:Cellular Senescence; D006801:Humans; D020930:MAP Kinase Kinase Kinases / Q000378:metabolism; D020935:MAP Kinase Signaling System; D009154:Mutation; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D020930:MAP Kinase Kinase Kinases; D018631:ras Proteins