Figure 6

Nutlin-3 induces H2AX phosphorylation and _H2AX foci formation independent of both p53 and MDM2 status. (A) HCT116^p53-/- cells were left untreated (unt) or treated with 100 μM Etoposide (Eto) or 10 μM Nutlin-3 (Nut) for 1 hour before the phosphorylation of H2AX (Ser139) was assessed using immunoblotting. Actin levels were used to assess equal loading. (B) Representative confocal microscopy images of γH2AX foci formation in HCT116^p53-/- cells treated with either 100 μM Etoposide or 10 μM Nutlin-3 for 30 minutes. (C) Representative confocal microscopy images of γH2AX foci formation in MEF^MDM2-/- cells treated with either 100 μM Etoposide or 10 μM Nutlin-3 for 30 minutes.