Fig. 2.

High-risk E6 and E7 can independently activate caspases upon differentiation. Western blot analysis was performed on cell lysates harvested from HFKs retrovirally transduced with pLXSN alone or pLXSN-HPV-31 E6, E7, or E6/E7. Lysates were harvested from undifferentiated cells (T0) and cells induced to differentiate in methylcellulose for 24 and 48 h. Primary antibodies used were specific for the active form of caspase-3 and caspase-7 and for procaspase-3 and -7. GAPDH was used as a loading control. The results are representative of three experiments by using two different HFK backgrounds.