UBE3A and cervical cancer: After validating the doxycycline-mediated expression system, we tested whether doxycycline-induced, acute DINO expression may override HPV16 E6/UBE3A-mediated TP53 inactivation and restore TP53 levels and/or activity in the HPV16-positive SiHa (Fig. 3A) and CaSki (Fig. 3B) cervical cancer cell lines.