TP53 and cancer: Ubiquitin-protein ligase E3A (UBE3A, also known as E6-associated protein [E6AP]), an E3 ubiquitin ligase, is best known for its role in the degradation of P53 in human papillomavirus (HPV)-mediated cancers [15], but growing evidence suggests that UBE3A also contributes to nonviral-related cancers [16].