DNA damaging agents and p53 do not cause senescence in quiescent cells, while consecutive re-activation of mTOR is associated with conversion to senescence
Figure 7.Serum stimulation of etoposide-locked WI-38t cells results in mTOR-dependent sensecence.A-B. WI38t cells were treated with 1μg/ml etoposide in the absence of serum as shown in Figure 6. Then, 10% serum was added either with 10 nM rapamycin (+R) or alone. No serum indicates that cells were continuously incubated with etoposide in serum free medium. 24 h after serum stimulation, cells were lysed and subjected to immuno-blotting as indicated (A). 4 days after serum stimulation cells were microphotographed (B).