XIAP and cancer: Furthermore, owing to the presence of RING domains, TRIM32 has been reported to function as an E3 ligase that interacts with and eventually ubiquitylates multiple substrates, including c-Myc [15], PIASy [protein inhibitor of activated STAT (signal transducer and activator of transcription) y] [16], Abi-2 [17], XIAP (X-linked inhibitor of apoptosis) [18], dysbindin [19] and desmin [20], and participates in various pathological processes ranging from cancer to muscular dystrophy.