UBR5 and ovarian cancer: Currently, the most well studied HECT domain E3 ligases that relate to chemoresistance are ubiquitin protein ligase E3 component n-recognin 5 (UBR5/EDD ), HECT, UBA, and WWE domain containing 1 (HUWE1/MULE) and HECT-Type E3 Ubiquitin Transferase Itchy Homolog (ITCH ), among which UBR5/EDD and ITCH have been reported to be implicated in ovarian cancer chemoresistance.