MDM4 and cancer: In previous studies, xCT/SLC7A11,14 FOXM1,15, 16, 17 Snail,18 PD‐L1,19 YAP1,20 SMAD2/3,21 Nur77,22 RAS,23 p53,24 MDMX,25 c‐IAP1/BIRC2,26 DEPTOR,27 Era,28 and TRAF3/629 were identified as OTUB1 substrates in cancer progression (Table S1).