Figure 9. Serum stimulation of etoposide-locked RPE cells results in mTOR-dependent senescence.

A-B. RPE cells were treated with 0.5 μg/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 immunoblotting as indicated (A). 4 days after serum stimulation cells were microphotographed (B).