Figure 4. Roscovitine induces RPA foci formation in HPV+, but not in HPV-, head and neck cancer cells.

A. HPV- SCC61 and HPV+ UMSCC47 cells were treated with 20μM of roscovitine for 24 hours. Cells were fixed and immunostained with γH2AX and RPA70 antibodies; representative images are shown. B. Quantification of RPA-positive cells from two independent experiments.